hybridfree/eevblog-posts huggingface dataset:
Best microcontroller for low noise environment - Page 1
Forum section: electronics / general

author: ezalys
author_rank: Frequent Contributor
timestamp: April 02, 2022, 12:04:21 am
content: I'm planning on using a microcontroller in a low noise/low emi design, and due to some supply constraints I want the microcontroller to share a ground plane with the converters. I will be carefully routing return currents and using space and sectioning things off to my advantage, but to go the last mile I want to minimize dI/dt. This means that I'm not interested in sleep/idle current, but the current demanded from the rail and injected into the various components during each clock cycle. Does anyone have any suggestions? The Ambiq apollo microcontrollers seemed like they might be appropriate, but don't appear to be on anyone's catalog. The only peripherals needed are USART and SPI. MSP430 seems like a potentially good default.

author: thm_w
author_rank: Super Contributor
timestamp: April 02, 2022, 12:26:16 am
content: How much power the MCU draws is not necessarily the main interest here.I would rather go with what you are familiar with, and consider using a low clock rate, limit bus speeds, low drive strength, etc.https://www.ti.com/lit/an/snoa382/snoa382.pdf?ts=1648780201122https://www.st.com/resource/en/application_note/cd00003981-emc-guidelines-for-microcontroller-based-applications-stmicroelectronics.pdfhttps://circuitcellar.com/resources/ee-tips/reduce-emi-on-micro-ee-tip-109/Looks interesting but I have not done this:https://www.maximintegrated.com/en/design/technical-documents/app-notes/2/232.html

author: David Hess
author_rank: Super Contributor
timestamp: April 02, 2022, 03:57:38 pm
content: Total EMI depends on dI/dT which is lower at lower voltages and with lower switched charge, and the number of dI/dT events which depends on clock frequency. So operate at the lowest suitable voltage and clock frequency. Lowest switched charge can be estimated by looking for parts which draw the lowest current for a given supply voltage and frequency; this depends on the number of transistors and process.
(AVR-DA) Equivalent Time Sampling - Page 1
Forum section: electronics / general

author: T3sl4co1l
author_rank: Super Contributor
timestamp: April 06, 2022, 01:29:45 pm
content: Just a cute byproduct of today's development work:Oh, one thing I forgot to adjust, the samples are in reverse order. Just mentally tack on a minus to the times then.They don't specify the sampling aperture in the datasheet (only the sample period, a couple clocks or more), but it does look to be comparable to the ADC clock. There is some evident rounding at the, whatever you want to call it, the rising zero crossing flat there (at ~12.8us), but hard to say how that translates into bandwidth.Why the dumbass waveform? First thing I tried, just happy that it works.The flat is dead time between triggers; it's just a triangle function triggered by the master timer (Ch2) (which also triggers the ADC, after a programmable delay). A square wave isn't actually much crisper, due to filtering in the circuit. Well, geh, let me bump that off and see what it does... ah yeah, that's a bit better isn't it. Seems to stabilize within about 4 clocks [of 24MHz], or ~170ns. So, presumably, analog bandwidth on the order of 3MHz. Which seems pretty typical, given the max sample rate is 130kSps.Note that, although the ADC is clocked from a prescaler, the prescaler is reset on start, so it's synchronous only to CLK_PER (24MHz here), and I have full  granularity on the equivalent time sampling here. Put another way, that's as if my TDS460 (actually 100MSps and 350MHz) said 50kSps, 3MHz BW and 24MSps effective.Tim
What is the equivalent of this EQ! chip in the attached image? - Page 1
Forum section: electronics / general

author: tomay3000
author_rank: Newbie
timestamp: April 07, 2022, 12:27:34 am
content: Hello,I need to buy the red framed chip in the attached image from Aliexpress.But I don't know any of its equivalents.Could you please tell me of any equivalent of it.TIA.NB:It is from anHP ProBook 440that has stopped working.

author: Nominal Animal
author_rank: Super Contributor
timestamp: April 07, 2022, 02:26:16 am
content: Looks very much like aRichtek RT8223MZQWpower supply controller IC.Unfortunately, I have no idea where to get one, or an equivalent; nor am I even completely sure that is what the chip is; sorry.

author: tomay3000
author_rank: Newbie
timestamp: April 07, 2022, 05:34:35 am
content: Indeed, it is the power related one.From this website:https://alexlaptoprepair.com/en/isl-maxiam-tps-ene-ite-bq-laptop-ic-equivalent/They say it should be : RT8223MGQWI think it is this one:https://www.aliexpress.com/item/1005001875405167.htmlCorect me if I am wrong.

author: Nominal Animal
author_rank: Super Contributor
timestamp: April 07, 2022, 07:22:17 am
content: Quote from: tomay3000 on April 07, 2022, 05:34:35 amAs thedatasheetsays, the difference between RT8223MGQW and RT8223MZQW is in the lead plating only; former (G) is "Green (lead and halogen free)", and the latter (Z) is "ECO (ecological, lead and halogen free)". Electrically, they should be perfectly equivalent and interchangeable; the difference only matters to those who manufacture lots of devices using these chips, I think.Quote from: tomay3000 on April 07, 2022, 05:34:35 amI think so too, assuming it is a genuine part and not a reject/fake. (As often mentioned here, a lot of ICs sold on AliExpress and eBay are fakes.)Please note that I am only a hobbyist, and I might be wrong!After you desolder the old chip, I personally would check the supply voltage and ground pads, if possible, before soldering the replacement chip.
Is this normal in SAR ADCs or am I dealing with missing counts? - Page 1
Forum section: electronics / general

author: Red_Micro
author_rank: Regular Contributor
timestamp: March 31, 2022, 06:41:25 am
content: I've set a 3x multichannel ADC, timer-triggered and DMA with STM32L476. My reference is 2.5V and my zero is Vref/2 = 1.25V. So when there's no input signal, I should measure 1.25V or ~2048 counts. This is what I see in the buffer:ADC = 2044; //input 0ADC = 2047; //input 1ADC = 2046; /input 2ADC = 2046; //Vref/2ADC tends to stay at 2044. The rest of the channels move around 2046-2047 but they don't go down to 2044. What I'm noticing is that missing count on ADC really makes a difference compared to the rest of the channels. Let's say you substract the reference value from the inputs, for ADC you get about 2044-2046 = -2 and that affects further calculations depending on how the counts processing is done. It will also offset the coming input signals.So my question would be if there's an efficient filter scheme that eliminates or mitigates this behavior to get a smoother "zero" for all the channels. If ADC stays at 2044 I don't know if a filter would help. At the end I'm not sure why the first channel differs a bit from the others when they all have the same signal.

author: wraper
author_rank: Unknown
timestamp: March 31, 2022, 06:49:54 am
content: This is a nonlinearity and/or offset, not missing counts.

author: wraper
author_rank: Unknown
timestamp: March 31, 2022, 07:01:48 am
content: Also if you sample directly from a resistive voltage divider bypassed by a capacitor in fast bursts and without an opamp buffer, input voltage will actually change. As each time you are charging sampling capacitor from the ADC input.
ARM assembler syntax query - Page 1
Forum section: electronics / general

author: AussieBruce
author_rank: Regular Contributor
timestamp: March 30, 2022, 09:17:26 am
content: Hi, I'm wading through a heap of system assembler files to sort out an IRQ problem on an ARM-7 target. Included is the following, they look like memory allocations. I can't find any reference to the 'b', is it shorthand for 'byte'? In fact, from the module context these should be exception/interrupt vectors, more than 8 bits. What do these lines do?undef_handler:b undef_handlerswi_handler:b swi_handlerpabort_handler:b pabort_handler

author: retiredfeline
author_rank: Frequent Contributor
timestamp: March 30, 2022, 09:20:40 am
content: Maybe branch unconditionally, i.e. handlers are infinite loops?

author: westfw
author_rank: Super Contributor
timestamp: March 30, 2022, 09:21:03 am
content: “B” is “branch” (unconditional)You are looking at tiny little default interrupt handlers that are short infinite loops.

author: abyrvalg
author_rank: Frequent Contributor
timestamp: March 30, 2022, 09:35:12 am
content: To clarify a bit: on ARM7 the vector table doesn’t hold addresses (unlike Cortex-M etc), the CPU jumps right into the table and each entry is a single instruction (so it is typical to use either “B real_handler” or “LDR PC, =real_handler”).

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 30, 2022, 05:36:48 pm
content: Quote from: retiredfeline on March 30, 2022, 09:20:40 amYes. This is not maybe, this is for sure.

author: rstofer
author_rank: Super Contributor
timestamp: March 30, 2022, 05:46:01 pm
content: Sometimes you will see something like:b 1bThis is a branch to the label 1 backwardb 1f is a branch to label 1 forwardhttps://stackoverflow.com/questions/27353096/1b-and-1f-in-gnu-assembly
stm32mp157 video port - Page 1
Forum section: electronics / general

author: bogdant
author_rank: Regular Contributor
timestamp: March 31, 2022, 11:55:38 am
content: As most of microcontrollers are no longer available from ST, I have a new project with stm32mp157 with linux as OS.So I am searching a solution for PC type video port: HDMI, DVI, DisplayPort or VGA to connect at stm32mp157 procesor.I found a solution on STM32MP157C-DK2 but the chip(SiI9022ACNU) used seems to be exotic.

author: errorprone
author_rank: Contributor
timestamp: April 01, 2022, 12:48:12 am
content: Other parts to look at are the TFP410 and ADV7533 but they seem to be out of stock at the moment.

author: bogdant
author_rank: Regular Contributor
timestamp: April 01, 2022, 05:01:37 am
content: for VGA I found this THS8136IPHP 3xDAC but it is only 10bit
Microwave energy detection - Page 1
Forum section: electronics / general

author: Sam21
author_rank: Newbie
timestamp: March 27, 2022, 11:59:48 am
content: Hello ,I am currently working in project, wherein I need establish a method to detect microwave energy, coming from a standard magnetron , and subsequently logg the same as an event.How about getting started with neon lamp and then building a aLDR based circuit to detect the microwave signal.This is considering that Neon lamp would get activated through microwave energy and this could further be detected by a light dependent resistor.Please float suggestions

author: madires
author_rank: Super Contributor
timestamp: March 27, 2022, 01:07:42 pm
content: I'll give you a hint for your homework: micowave leakage detector.

author: MathWizard
author_rank: Super Contributor
timestamp: March 27, 2022, 02:57:03 pm
content: I have 2 "magnetron" units, I don't want to throw them away, if I travel back in time, I should take them with me....

author: mazurov
author_rank: Frequent Contributor
timestamp: March 28, 2022, 06:36:59 pm
content: High energy output of a magnetron can be easily detected with a fluorescent bulb (not necessarily a working one). Youtube has plenty of videos demonstrating the effect.
Realtek RTL8309M-CG datasheet - Page 1
Forum section: electronics / general

author: Deni
author_rank: Regular Contributor
timestamp: March 25, 2022, 06:55:15 pm
content: I am looking for a detailed datasheet for this 8-port switch. One I have does not show PHY register map and some other stuff. I googled my brains out,but could not locate it. We have some issues with the board designed around it and I would appreciate if somebody can share it or at least point in theright direction. Realtek does not respond, since we're not large OEM, tried that already... Again, any help appreciated.

author: amyk
author_rank: Super Contributor
timestamp: March 26, 2022, 12:36:07 am
content: Could it be the same as the RTL8309SB ?

author: Deni
author_rank: Regular Contributor
timestamp: March 26, 2022, 06:15:49 am
content: No, they're not the same. I have datasheet of that one, but I do not know if register map matches.Btw. - I saw that there is some stuff on CSDN site, but I am not a member. Tried to register, but my Chinese is a bit rusty

author: DavidAlfa
author_rank: Super Contributor
timestamp: March 26, 2022, 01:26:40 pm
content: Isn't theRTL8309Nthe same thing?

author: Deni
author_rank: Regular Contributor
timestamp: March 26, 2022, 02:13:22 pm
content: Nope - RTL3809N does not have 9'th port which RTL3809M-CG has . It can be configured to act as a PHY for direct connection with CPU - and we use thatfunctionality. And actually, that's where we have issues I want to clear out.

author: mon2
author_rank: Frequent Contributor
timestamp: March 26, 2022, 03:26:05 pm
content: How could you / your group / company select this device for a design and do so without proper factory support ? The device is in distribution so you should reach out to the supplier of these parts for factory support.Keep sending Realtek emails till they respond. Don't give up till they provide the full support to use their shitware devices. So many vendors like them in the market - you have ample choices to migrate away from them. Trying to hunt down the datasheet after the design is completed is not the proper approach.If needed, hire a Chinese interpreter and have them call their HQ for support. We have done this with success with some of the vendors we wanted to work with. In return the factory then supplied English speaking staff members to move forward.Waaay too much vendors want you to buy a container load of this or that and run as fast as possible from any responsibility of support. Very common trend in Asia. Locally, the markups are so high, they are using the profits to fuel their luxurious lifestyles while engineers slug it out to fix the buggy silicon.
USB not recognized for pic18F14K50 - Page 1
Forum section: electronics / general

author: Aankur
author_rank: Newbie
timestamp: March 26, 2022, 03:43:04 am
content: HelloI am trying to make USB connection to PIC18f14k50.Following are connections :-Pin 1 (Vdd)------>5VPin 2 & 3 -------->External crystal oscillator (20MHz)Pin 4 (MCLR)------------->Pulled high with 10KPin 20 -------------------->GNDPin 17---------------------> capacitor (0.1UF)First I try to upload the bootloader through MPLAB IDE through pickit3.After downloading the bootloader, I connect the USB to pic18f14K50.Doing this, my windows 10 gives a message "USB not recognized"Any help in this regard is appreciable.Thanks

author: Ian.M
author_rank: Super Contributor
timestamp: March 26, 2022, 04:49:27 am
content: You can't use a 20MHz crystal and USB on that PIC. See datasheet, page 24. Fit a 12MHz crystal and increase your pin 17 capacitor to 0.33uF and it should 'just work'.
Read protection fuses in the NXP i.MxRT microcontrollers - Page 1
Forum section: electronics / general

author: luiHS
author_rank: Frequent Contributor
timestamp: March 04, 2022, 03:42:27 am
content: HiDoes anyone know how to activate the read protection fuses in the NXP i.MxRT microcontrollers?In the NXP Kinetis I did it by creating the project to load the program into the microcontroller using SEGGER's Jlink hardware programmer, there a project could be created by activating security (protects the microcontroller against reading so that they cannot read the program).On the Kinetis, I read but didn't test that fuses can also be modified in the Flash_Config parameter of the startup source file in MCUXpresso, but I don't see anything like that for MIMXRTs.I also see that for the ST STM32, using the STM32 Cube Programmer program, the fuses can be modified to protect the microcontroller against reading, in the Option Bytes > Read Out Protection menu option.Regards

author: newbrain
author_rank: Super Contributor
timestamp: March 04, 2022, 10:36:47 am
content: To the best of my knowledge, i.MX RT MCUs only have external flash memory.That applies also to the 4 MB 'on-chip' flash models (1024 and 1064) where a QSPI flash chip is packaged together with the MCU chip.A read protection does not make much sense in this context, instead, i.MX RTs support encryption of the external memories:as the external flash is encrypted, the code will reside in RAM at runtime and needs to be decrypted while being copied to RAM.Now, how to set this up is something I do not know, you need to search info on HAB - High Assurance Boot for your specific model.

author: luiHS
author_rank: Frequent Contributor
timestamp: March 04, 2022, 05:54:17 pm
content: Quote from: newbrain on March 04, 2022, 10:36:47 amThank you, yes, surely it will be as you say, since everything is encrypted because it is in external flash, reading protection makes no sense because the flash cannot be protected, I suppose.I'll have to see how the object code encryption works, once the program is compiled. I'm still building prototype boards with the RT1064, I haven't created the programs or tested the encryption yet.

author: mac.6
author_rank: Regular Contributor
timestamp: March 07, 2022, 08:50:00 pm
content: For this you need access to the i.mxRT1062 security reference manual, unfortunately it's under NDA.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 07, 2022, 08:59:36 pm
content: That is pretty good to know.External flash is a convenient way of having ample flash memory while costing less for the MCU vendor. But it comes with this problem of security. Sure you can mitigate this by encrypting the content, but if doing so requires going through hoops with the vendor, that's a definite minus point compared to other vendors.I have evaluated the RT1062 but haven't gone as far as thinking about this issue so far, so this thread comes at the right time.

author: mac.6
author_rank: Regular Contributor
timestamp: March 29, 2022, 08:30:57 pm
content: You can probably find some information into the SPSDK, but it doesn't replace the proper SRM.https://github.com/NXPmicro/spsdk
ECC Data Winbond W25N01GV - Page 1
Forum section: electronics / general

author: iamno3
author_rank: Newbie
timestamp: April 05, 2022, 06:48:33 am
content: I understand that ECC is for correcting data. For example I read sector 0 from nand flash and got ECC status register : 1~4 bit ECC correction (0,1) then I read ECC code from spare area @address 0x800 byte 0x08~0x0D (exampleAE 18 75 AC 3C 35). What should I going to do with this ECC code ? How to (step by step) correct the sector 0 data ?

author: ataradov
author_rank: Super Contributor
timestamp: April 05, 2022, 07:09:58 am
content: You don't need to do anything with that data. If the status bit indicates that there was one corrected error, then the data you have is valid. Depending on the application you may want to erase and overwrite the affected sector.If you've got the status that there was more then one error, then the data is not valid and not recoverable.ECC code is written and used for correction automatically provided that ECC is enabled (ECC-E=1).

author: iamno3
author_rank: Newbie
timestamp: April 05, 2022, 07:23:24 am
content: Hello thanks for replying.So you mean that the data already correct automatically by nand flash itself ?

author: ataradov
author_rank: Super Contributor
timestamp: April 05, 2022, 07:26:49 am
content: Yes. ECC needs to be enabled during the write to set ECC bits. And ECC needs to be enabled during the read to use them.You can disable ECC during the read of the data that was written with ECC enabled, but there won't be correction applied in that case.
Cable for CAN bus FD and UART cable. - Page 1
Forum section: electronics / general

author: luiHS
author_rank: Frequent Contributor
timestamp: March 19, 2022, 10:23:12 pm
content: HiCould two CAN bus FD devices be connected with an unshielded cable? A twisted pair for data and 2 wires for ground and power. My idea is to use 2mm pitch SMD connectors on the PCB and a cable with 2mm unshielded female connectors. The length would be about 80cm.And for communications using the UART, increasing the level of data signals to 12v, would it be safe to use unshielded cable? Same length of about 80cm.Thx

author: Sal Ammoniac
author_rank: Super Contributor
timestamp: March 19, 2022, 10:51:58 pm
content: I have every wall switch in my house wired with daisy-chained unshielded CAT5 and I use one of the twisted pairs for power and another for CAN. Each switch has a small PCB that listens on the CAN bus for instructions to turn the switch on or off (typically to turn on ceiling lights). This bus runs throughout my house and the total length of the cabling is perhaps a hundred meters.Note that this is standard CAN running at 250 kbps, not CAN FD.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 19, 2022, 11:18:50 pm
content: For UART, RS232 works at longer distances than 80 cm, so sure. What's the data rate?I'm pretty sure CAN FD should have no problem at all with unshielded cables, especially over such short distances.Another question is EMI, though - and I mean here, more the emissions than the susceptibility. What's the final environment?

author: luiHS
author_rank: Frequent Contributor
timestamp: March 20, 2022, 01:24:04 pm
content: Quote from: SiliconWizard on March 19, 2022, 11:18:50 pmThe speed for the UART, I'll test it at 115000 bps, although it could run slower if needed.The environment is somewhat noisy at the electromagnetic level, because there are several electromagnets that are activated during the process. That's why I thought of using shielded cables, and adding ferrites at the end of each cable, as well as EMI filters on the supply voltage of each board.

author: Rudolph Riedel
author_rank: Regular Contributor
timestamp: March 21, 2022, 06:25:26 am
content: Quote from: luiHS on March 19, 2022, 10:23:12 pmYes of course, it is designed to use unshielded cables.I am using CAN-FD over standard unshielded CAN cables with 500k/500k to 1M/8M just fine.
Has anybody used Rust language on STM32 or ESP32? - Page 1
Forum section: electronics / general

author: FlyingDutch
author_rank: Regular Contributor
timestamp: March 18, 2022, 06:07:53 am
content: Hello Forum,has anybody used Rust compiler for small MCUs Like STM32 or ESP32. Today I was watching tutorials about Rust language and I am curious how programs written in this language prove itself on small MCUs (like smaller series of STM32 or ESP32(Xtensa). I am also curious about availability of libraries for control hardware (like for example ADCs or varoius sensor) from crate.io, or "unsafe" code and C library has been used often. I understand that Rust language is much more safe than C/C++ (memory safe and threads safe), but I would like to know if in your opinion it is worth to switch from C++ to Rust (in context of smaller ARMs)? I am going to try Rust on STM32 and ESP32 within several next days.Best Regards

author: brucehoult
author_rank: Super Contributor
timestamp: March 18, 2022, 08:07:41 am
content: People have been using Rust on quite a number of different RISC-V microcontroller boards and CPU types for several years now. Many have as little as 16k SRAM.https://github.com/riscv-rust/

author: FlyingDutch
author_rank: Regular Contributor
timestamp: March 18, 2022, 08:20:47 am
content: I have logan-nano board with RISC-V after STM32 I would try this board too.Best regards

author: lucazader
author_rank: Regular Contributor
timestamp: March 19, 2022, 09:04:16 am
content: Would be great to see how you get on with this.What pitfalls you find. what benefits traps other things like that!Good luck I'm interested to see how you get on.
PIC: MPLABX 6 Stuck at select compiler  - Page 1
Forum section: electronics / general

author: Graffite
author_rank: Contributor
timestamp: March 18, 2022, 06:58:14 pm
content: Hello all. I installed Microchip MPlab X 6 on my desktop PC to make it easier to use than my 15" laptop but the software gets stuck at the select compiler section. It works fine on my laptop!I have tried reinstalling etc but its still the same.Any ideas.Sorry if this is not the best place to post this.Geoff

author: hans
author_rank: Super Contributor
timestamp: March 18, 2022, 09:47:27 pm
content: Have you installed the relevant compilers?They are not part of the MPLABX download. You have XC8 XC16 and XC32 for 8, 16 and 32-bit microcontrollers, respectively.

author: Graffite
author_rank: Contributor
timestamp: March 18, 2022, 10:25:39 pm
content: Yes they are all showing up fine in the options menu with each of the paths indicating correctly. The software works fine on my laptop and was installed in the same manner.Thanks for the reply.

author: mazurov
author_rank: Frequent Contributor
timestamp: March 19, 2022, 12:42:32 am
content: How does "gets stuck" look like - can you post the error message?

author: Graffite
author_rank: Contributor
timestamp: March 19, 2022, 02:01:50 pm
content: I start a new project. Select the IC and move to the compiler section. The software shows please wait but never returns the compiler selections. The image is a screen snip

author: JPortici
author_rank: Super Contributor
timestamp: March 19, 2022, 05:03:49 pm
content: do you have any notifications? (those could be errors)you could try and delete the cache folder

author: Graffite
author_rank: Contributor
timestamp: March 20, 2022, 06:23:28 pm
content: Hello. Thanks for your input. I think the issue is to do with the machine have other compilers on it. From Avr studio, CoCOx and Ride IDE. Its seams to have picked up everything. If I remove them it goes a bit further though and I get some errors, (Cant find the device support). I will have a look on my other machine and see what's needed just for a basic setup.

author: Graffite
author_rank: Contributor
timestamp: March 20, 2022, 06:27:26 pm
content: Hey we are back in action with just the X8 and X16 showing in the compiler paths. Many thanks all.
ARM is planning to cut up to 15% of its workforce - Page 1
Forum section: electronics / general

author: voltsandjolts
author_rank: Unknown
timestamp: March 15, 2022, 10:44:10 am
content: Due to Nvidia sale falling through...https://www.theguardian.com/business/2022/mar/15/uk-chipmaker-arm-cut-jobs-sale-uk-us-nvidiaPerhaps Softbank had tried to 'big it up' prior to sale attempt to maximise sale price and this is returning to something more sustainable.Anyways, back to hunting down some 32F4's...heh

author: Rick Law
author_rank: Super Contributor
timestamp: March 15, 2022, 05:51:39 pm
content: As always, job lost is sad particularly for those affected regardless of where. May be for long term survival, ARM should consider getting into defense applications. Defense related would have a better chance of staying on-shore in Britain/USA. Perhaps some cruse missile applications and the likes should like a good CPU and other electronics.I hope those affected can get by without being hurt too much.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 15, 2022, 05:59:27 pm
content: That sucks. But it's deluded to think that wouldn't have happened if the sale was completed. Sales like this always come with significant restructuration - which means a lot of job cuts as well. The only big difference in this case is that people usually get more money when being laid off.
MQTT protocol - Page 1
Forum section: electronics / general

author: BlogRahul
author_rank: Regular Contributor
timestamp: March 14, 2022, 12:49:45 pm
content: I have heard a lot about the MQTT protocol I am trying to understand why MQTT protocol used in IoT insted of HTTPs.

author: Berni
author_rank: Super Contributor
timestamp: March 14, 2022, 01:08:10 pm
content: MQTT consumes less data traffic, is simpler to implement for a microcontroller and allows bidirectional communication (so when someone publishes new data everyone who wants it instantly gets the data forwarded to them, in http you have to poll the server)

author: Siwastaja
author_rank: Super Contributor
timestamp: March 14, 2022, 02:55:10 pm
content: Hypertext Transfer Protocol aka. HTTP is designed for servingweb pagesfrom a single server to multiple clients.MQTT is designed for sending small measurement data packets in whatever (usually efficient) format to a central server, which then further distributes the messages to the subscribers.Quite a different use case.

author: jancumps
author_rank: Unknown
timestamp: March 14, 2022, 03:59:50 pm
content: Yes.MQTT is closer to a Java Message Server and the likes, where you can publish messages, and subscribe to messages. You talk to a distribution service, and indicate a subject (topic). You don't (have to) know the final interested party/ies.HTTP is closer to a remote procedure call. You talk to a single end point.
Can I substitute Attiny841 for Attiny85 - Page 1
Forum section: electronics / general

author: bigjoncoop
author_rank: Regular Contributor
timestamp: March 13, 2022, 12:35:26 am
content: hey fellaz,i was able to purchase a bunch of Attiny841 IC's recently. I found a diy project that's using a Attiny85 and was wondering if could use the Attiny841 instead with out any modification?and does anyone know of a chart or simple way to easily determine if which attiny and be substituted for which?

author: MarkF
author_rank: Super Contributor
timestamp: March 13, 2022, 02:52:40 am
content: I haven't worked with the ATtiny families.You just have to search the datasheets.However, I will let you answer your own question:

author: hans
author_rank: Super Contributor
timestamp: March 13, 2022, 08:41:11 am
content: No those parts have 2 different datasheets.You can probably port over many peripherals, as they will be coded similar or even use the same register layout but with slight deviations.

author: Kleinstein
author_rank: Super Contributor
timestamp: March 13, 2022, 09:19:32 am
content: The Atiny841 has a different number of pins with supply at non compatible pins - so there have to be HW changes.The SW side would very likely also need changes. Here at least the pheriphery is still very similar (though 16 bit timers instead of 8 bit ones). So the port of the SW should be resonable simple, but still a little work and the code may end up slightly longer.

author: bigjoncoop
author_rank: Regular Contributor
timestamp: March 14, 2022, 06:50:07 am
content: @Kleinstein@hans@MarkFThanks for your replys.But i should have explained my question better. I realize they have different amount of pins and pinout.What I should have asked is, can I run the same sketch / code on them.

author: sleemanj
author_rank: Super Contributor
timestamp: March 14, 2022, 07:27:09 am
content: That all depends on the code.Since you say "sketch" then I would guess we are talking about Arduino. When using an appropriate core (https://github.com/SpenceKonde/ATTinyCore) then high level functions and libraries will **probably** work.Low level stuff will probably **not** work, as registers and so forth will be different.

author: westfw
author_rank: Super Contributor
timestamp: March 14, 2022, 08:53:10 am
content: All that said, the tiny841 has MORE features than the tiny85, except for the high speed timer clocking. So it should be easier to get a t85 sketch working on an 841 than the other way around.
[SAMC] DAC clock source and speed - Page 1
Forum section: electronics / general

author: Simon
author_rank: Unknown
timestamp: March 11, 2022, 01:52:22 pm
content: I'm looking at the DAC on the SAMC series of microcontrollers. I have not come across any clock speed requirements for the DAC. I also do not know how long it takes for a conversion to happen in clock cycles.

author: MK14
author_rank: Super Contributor
timestamp: March 11, 2022, 02:18:26 pm
content: Fromhttps://ww1.microchip.com/downloads/aemDocuments/documents/MCU32/ProductDocuments/DataSheets/SAM-C20-C21-Family-Data-Sheet-DS60001479J.pdfWhen you search for ' GCLK_DAC ', it seems to say:QuoteWhich since it seems to be 350kHz, max DAC (sampling/update) data rate. 4 x 0.350 = 1.4 MHz minimum, and the maximum is stated as 48 MHz.MAX is given as:QuoteQuoteWhich (at a somewhat quick look at the datasheet), is a fixed rate, independent of other settings, unless you disable/stop it, e.g. for power saving (sleep/idle) reasons.But I'M NOT 100% sure about that (i.e. fixed at 350 kHz, while running).They seem to prefer/intend for you to use its interrupt or DMA, to use it, in a time controlled manner. But I suppose you could still use it manually in the software.

author: Simon
author_rank: Unknown
timestamp: March 11, 2022, 02:30:47 pm
content: Ah, good detective work, I thought the DAC would be covered in the analogue section of electrical specs completely.So there is still no clue as to the actual clock cycles required to carry out a conversion other than maybe the dropping of a hint in the voltage pump settings. I don't need speed but have so far just run everything off the one clock channel at 48MHz

author: ataradov
author_rank: Super Contributor
timestamp: March 11, 2022, 05:10:22 pm
content: Conversion time is variable and depends on the previous value. You can clock the DAC with 48 MHz, there is no issue doing that. If you need specific sampling rate, you must use external timing trigger, like a timer. And if you need regular updates at high rate, it is better to use DMA and trigger DMA transfers from the timer.

author: MK14
author_rank: Super Contributor
timestamp: March 11, 2022, 08:26:12 pm
content: More information about the DAC, seems to be here:https://microchipdeveloper.com/32arm:samd21-dac-overviewQuoteAlso, this one (about driving software and stuff):http://ww1.microchip.com/downloads/en/DeviceDoc/Atmel-42110-SAM0-Digital-to-Analog-(DAC)-Driver_Application%20Note_AT03244.pdf

author: Simon
author_rank: Unknown
timestamp: March 12, 2022, 02:26:53 pm
content: Quote from: ataradov on March 11, 2022, 05:10:22 pmNo speed is not an issue, just avoiding more clocks than I need although there is little reason to have a 48MHz clock at all so could reduce it.
RPI CM4 doesn't boot - Page 1
Forum section: electronics / general

author: reyntjensm
author_rank: Regular Contributor
timestamp: March 09, 2022, 03:56:26 pm
content: I made a design with a rpi CM4 module connected to my own PCB. As far as i know all the connections to the CM4 module are correct. Sadly enough the CM4 doesn't power/boot up. I can measure 5V at some caps on the CM4 module. The other caps show no voltage at all. I don't understand why the CM4 module doesn't generate the 3,3V rail. The troubleshooting guide on the RPI website doesn't help me also. I've checked the Global_EN signal and this is high, the guide says if 5v is available the other rails should power up. So i don't see any reason why the CM4 module doesn't generate it's own voltage rails. Any advice on this?

author: dmendesf
author_rank: Frequent Contributor
timestamp: March 09, 2022, 08:59:10 pm
content: Do you have a carrier board to test the CM4? Can you share schematics/photos of the assembly?

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 09, 2022, 09:11:18 pm
content: A schematic of your own board would help.Have you connected the Global_EN pin to anything externally?

author: fchk
author_rank: Frequent Contributor
timestamp: March 10, 2022, 03:27:27 pm
content: Use the CM4 IO Board as a reference.https://datasheets.raspberrypi.com/cm4io/cm4io-datasheet.pdfYou will need more than only 5V in order to boot the CM4. Look it up in the schematics on pages 9++.fchk

author: eugene
author_rank: Frequent Contributor
timestamp: March 10, 2022, 07:54:00 pm
content: According to theCM4 Datasheet, GPIO_VREF must be connected to either 3.3V or 1.8V. See page 9 and 10. Also the table on page 19.
[ATSAMD10D13AS] Sleep mode and receiving multiple data packets with I2C - Page 1
Forum section: electronics / general

author: WILDERNESSBAGEL
author_rank: Contributor
timestamp: March 11, 2022, 11:05:55 am
content: The SAMD10 goes to sleep and is woken up by I2C on address match. I am just wondering if there is a way to set up the communication so I can send multiple data bytes without having to wake up the device until the transaction is over. So for example now I have this on the master side (arduino):Code:typedef union test{uint32_t toSend;uint8_t mBytes[sizeof(uint32_t)];}test;for(uint8_t i = 0; i < sizeof(uint32_t); ++i){Wire.beginTransmission(0x29); // transmit addressWire.write(t.mBytes); // sends refresh time in msWire.endTransmission();}So everytime I want to send data to the device I need to send the address first and then check on the slave check if all bytes have been received. I would like to make the master code look like this:Code:Wire.beginTransmission(0x29); // transmit addressfor(uint8_t i = 0; i < sizeof(uint32_t); ++i){// or something likeWire.write(t.mBytes); // sends refresh time in ms}Wire.endTransmission();
CubeIDE and vectors. What include is needed? - Page 1
Forum section: electronics / general

author: Watth
author_rank: Frequent Contributor
timestamp: March 06, 2022, 07:18:05 pm
content: Hello EEVpeople,In my daring attempts with STM32CubeIDE, I'm trying to play with vectors.Defining a vector withCode:vector<uint8_t> numbers;will generate an error :Code:'vector' undeclared (first use in this function)So I tried to add at the beginningCode:#include <vector>but I then haveCode:Unresolved inclusion: <vector>Yes: I'm a noob that has only touched Arduino IDE for the last years, and who then forgot how to you a grown-up's IDE.How can I make it work?Anyway, thanks for reading.

author: uer166
author_rank: Super Contributor
timestamp: March 06, 2022, 07:22:53 pm
content: Seems like you're using a C++ construct in a C environment, which would never work of course. Maybe take a look at some C language references/tutorials for pointers (heh) on how to use the language.

author: voltsandjolts
author_rank: Unknown
timestamp: March 06, 2022, 07:49:11 pm
content: I've never used CubeIDE but this might help:https://shawnhymel.com/1941/how-to-use-c-with-stm32cubeide/Note the explicit selection of C++ when creating your project.

author: Watth
author_rank: Frequent Contributor
timestamp: March 07, 2022, 11:21:36 am
content: Well I set the project to run in c++.

author: Watth
author_rank: Frequent Contributor
timestamp: March 07, 2022, 03:56:45 pm
content: Thanks! That link is very helpful.So when you set a project in C++, you just have to name the files (including main) with the proper extension.Any way, as your link indicated, I might as well keep the main in C and call parts in C++ (e.g. parts with these new fangled things such as vectors) within other files in C++. And, by exemple, calling class methods using wrappers.

author: westfw
author_rank: Super Contributor
timestamp: March 08, 2022, 11:16:49 am
content: AFAIK, it’s much easier to call C from C++ than the other way around, implying that main() should be C++
To what part of the microcontroller does vdd_3 supply? (stm32f103rct6) - Page 1
Forum section: electronics / general

author: teslinius
author_rank: Regular Contributor
timestamp: March 08, 2022, 08:07:45 am
content: I was interested what part of the microcontroller does vdd_3 supply, but i couldn't find any information about this information.

author: eutectique
author_rank: Frequent Contributor
timestamp: March 08, 2022, 11:03:16 am
content: Reference manual, document RM0008 Rev 21, page 68, figure 4 "Power supply overview".
Convert encoder 1Vpp to UVW - Page 1
Forum section: electronics / general

author: thewho333
author_rank: Newbie
timestamp: March 08, 2022, 07:42:25 am
content: Hello everyone!I need to convert my encoders 1Vpp sine/cosine differential output to UVW that my servo drive can use for rotor position.So far I have combined and amplified the differential signal with a LM358 op-amp.And my plan is to use a microcontroller for the sine/cosine calculation and subsequent conversion to rotor angle > electrical angle(div by pole count) > UVW commutation signals.I think that the servo drive only uses UVW to get the initial position and then reverts back to counting the incremental encoder signals. But I'm not sure, so to be safe I'd like to get the conversion fast enough to not loose sync at 3000rpm. (And 8000rpm for the spindle motor)So to the question:How do I combine and convert sine and cosine (0-1023) to an angle (0-359) fast enough? Where "fast enough" is 8000rpm / 60 = 134Hz * 8 poles * 6 uvw = 6432Hz. In other words, the loop needs to run at least 6432 times a second.I did some research and I probably want to use a sine lookup table?(I'll attach an example image that shows the signals)Programming is really not my strong suite so I would like to do it with an arduino compatible mcu 😅 stm32f103 maybe?

author: Ian.M
author_rank: Super Contributor
timestamp: March 08, 2022, 08:16:10 am
content: No, you don't want a sine lookup table as if you had one you'd have to do two reverse lookups to get the angle then a bunch of comparisons to get U,V and W.How fast do you want? Throw a large enough ROM lookup table at the problem and you can generate U,V & W signals as fast as you can read two channels via the ADC. Just concatenate the two ADC results with some of the low bits sliced off and use them as the address in the lookup table. The table stores precomputed U,V W and an error bit in a nibble. The error bit is set for addresses that aren't close enough to the expected sine/cosine circle from the encoder, and indicate an encoder fault. To save memory, pack the table two nibbles to a byte and slice off one bit of the combined address to select which nibble to return.Throw hardware at the problem e.g. two Flash ADCs, a fast ROM and a sample clock generator, and you could update U, V & W at well over 10MHz!

author: thewho333
author_rank: Newbie
timestamp: March 08, 2022, 10:01:56 am
content: Thank you!That is obviously the smarter way to do it
ARM hardware DSP Image codec support???...... - Page 1
Forum section: electronics / general

author: Smokey
author_rank: Super Contributor
timestamp: March 03, 2022, 11:47:11 pm
content: Does anyone know of a software library that uses ARM hardware DSP instructions to accelerate image decompression? Preferably on the lower cost cores (M4, M33, etc).I really don't want to switch processors only to find out I now need to become a DSP expert and write my own optimized decompression library.

author: Smokey
author_rank: Super Contributor
timestamp: March 07, 2022, 10:00:21 am
content: While not ARM DSP specific, it looks like LZ4 has a fast decompression. I need to get that running and see how it does on images, and how fast it runs.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 07, 2022, 06:05:52 pm
content: From my experiments, LZ4 is indeed fast, but relatively poor in terms of compression ratio, in particular on images. (But that may depend on the content of your images, I tried it on photos.)Keep us posted though.You could otherwise consider QOI - which was mentioned in this forum a while ago. Much simpler and fast. It's pure C, so no DSP instructions, but it might be good enough for your needs. You could always modify it and replace some operations using DSP instructions through GCC builtin functions, which would be the easier path. The code is simple enough IMO not to be intimidating for this kind of endeavor.https://www.eevblog.com/forum/microcontrollers/more-compression-codecs/Don't get put off by my comments there - the fixes are easy to do, and maybe the author has already done so (didn't check lately.) It otherwise works plenty fine from my experiments.

author: Smokey
author_rank: Super Contributor
timestamp: March 07, 2022, 11:32:41 pm
content: Thanks for the feedback. I don't want to fragment the info about QOI too much, so I'll keep the discussion about that in the link you posted.
Infieneon takeover of Cypress PSOC series - Page 1
Forum section: electronics / general

author: labnet
author_rank: Contributor
timestamp: February 22, 2022, 05:34:07 am
content: Does anyone have inside information on the Infineon takeover of Cypress.All the PSOC5LP series of processors are now unavailable with Infineon not even being able to give a lead time on their availability.Its a disgrace when you have spent over $100k on developing a product.Seems a similar situation with PSOC 6 family.Did they screw up the take over? or do they just not care and want to let the PSOC line wither on the vine and die.

author: lucazader
author_rank: Regular Contributor
timestamp: February 22, 2022, 06:37:17 am
content: This is probably more to do with the general component shortage that is hitting most microcontroller manufacturers at the moment/for the least year or so.However i dont have any specdific knowlege on Infineon/cypress.

author: GromBeestje
author_rank: Frequent Contributor
timestamp: March 05, 2022, 03:49:51 pm
content: I believe Infineon's own XMC4 series are also out of stock, so I'd say it is the silicon crisis, not cypress specific.
arduino volt/amp meter - Page 1
Forum section: electronics / general

author: m3vuv
author_rank: Super Contributor
timestamp: March 09, 2022, 07:37:35 pm
content: Hi all,i am building a new bench psu,i want to build a volt/ampmeter for it using a 16/2 lcd with ic2 interface and a arduino nano,i dont want to use a current sense modual tho,just a current sense resistor,idealt it will have a range from 0-50v and 1ma -20amps any idea where to look for a link etc for this ? TIA.

author: rstofer
author_rank: Super Contributor
timestamp: March 09, 2022, 10:15:03 pm
content: If you measure current in the ground side of a device, it's ground voltage obviously increases. For a light bulb it may not matter, for some kind of logic device it may make a big difference in output voltage to the next device. If the drop is a low number of millivolts, no problem but, of course, the ADC won't even see the voltage. You need to work out what size sense resistor will give as many bits of resolution as you require. Even then, range switching may be required. You can count on needing gain and an op amp.For low side measurements:https://www.instructables.com/DIY-Current-Sensor-for-Arduino/
NHE and FWE - Page 1
Forum section: electronics / general

author: CyberGen
author_rank: Newbie
timestamp: February 28, 2022, 03:05:57 pm
content: Hi there ;I have two chipsets. It's the NHE6300ESB on my motherboard, but I got the FWE6300ESB when I ordered it.What is the difference between NHE6300ESB and FWE6300ESB?

author: hans
author_rank: Super Contributor
timestamp: February 28, 2022, 09:55:11 pm
content: Different steppinghttps://ark.intel.com/content/www/us/en/ark/products/27663/intel-6300esb-io-controller.html-> "Ordering and Compliance"

author: CyberGen
author_rank: Newbie
timestamp: February 28, 2022, 11:08:40 pm
content: hello, thanks for the help, I guess there is no difference between the chipsets. production-related codes or I could not understand.
Uninstall TL866 II+ - Page 1
Forum section: electronics / general

author: PerranOak
author_rank: Frequent Contributor
timestamp: February 27, 2022, 05:10:30 pm
content: I installed the TL866 II+ in the C:\Program files directory thinking it would install in a sub-folder. It just seems to have dumped it into the root of Prog files - annoying.Anyway, it can't save the last chip read/prog as it can't write to that folder. So, I want to uninstall it and reinstall elsewhere so it can write to it - don't want to mess with write access on the prog files folder.Problem is that the prog doesn't appear in the list of progs installed!How can I uninstall it please?Cheers.

author: Shock
author_rank: Super Contributor
timestamp: February 27, 2022, 08:01:06 pm
content: Create a folder and install or unpack it in that folder. Then carefully compare files against where you accidentally installed or unpacked them last time, remove the accidental install one by one being more careful this time.Edit:Not all programs have installers or write to the registry but in most cases if there is no uninstaller a second installation overwrites anything pertinent to normal operation of the program.

author: PerranOak
author_rank: Frequent Contributor
timestamp: February 28, 2022, 03:47:20 pm
content: Did all that and it's all working well and everything is neat and tidy.Brill, cheers mate.