Are these microcontroller boards? - Page 1
Forum section: electronics / general

author: highcap
author_rank: Contributor
timestamp: August 07, 2025, 02:32:58 pm
content: And what are their uses? Could not find any info about them online.Thank you for any input.

author: Psi
author_rank: Super Contributor
timestamp: August 07, 2025, 02:44:16 pm
content: Quote from: highcap on August 07, 2025, 02:32:58 pmThey're both microcontrollers.The first/last one with an ATMega16 yes, and its still usable today without much effort.The other one with the C517A is a bit too old to bother doing anything with, it looks to need external memory/flash. (The ATMega16 has that all contained inside)No idea what they are supposed to do. C517A is often used for motor control systems. but that doesnt mean that's what it's being used for here.At least the ATMega16 board has some LEDs and buttons. Not sure why it has a USB socket. Maybe it's just for power. Someone could have implemented USB in software I guess.

author: highcap
author_rank: Contributor
timestamp: August 07, 2025, 02:52:46 pm
content: Still good news, thank you.How would I go about connecting/making use of the ATMega one? It has an USB port and a DC power jack (probably 5V).

author: Psi
author_rank: Super Contributor
timestamp: August 07, 2025, 02:58:50 pm
content: Quote from: highcap on August 07, 2025, 02:52:46 pmThe 2x5 pin header bottom right has a very high chance of being a standard 10pin AVR debug/programming header.There's many options for programming ATMega chips using the standard 10pin header.

author: Psi
author_rank: Super Contributor
timestamp: August 07, 2025, 03:05:54 pm
content: I did some searching and you can pretty easily get the email address of the guy who made that ATMega16 board.Maybe he can send you the schematic, or just tell you what it is.Given the markings on it I think it's from a university/tech college project.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 07, 2025, 06:04:04 pm
content: Both PCB's are so easy to reverse engineer that it's barely worth attempting to find info on the development boards.https://duckduckgo.com/?t=h_&q=microwilli+development+board&ia=webhttp://d.pcnews.at/ins/cds/009/_pdf/n740060.pdfFor the atmega16. I've got a few of those too, but my preference for development boards is to use something breadboard compatible. You can stick an atmega16 directly into a breadboard, but for more reliability, it's good to lift the pins for the crystal and solder the crystal + caps directly to the IC. If you run it from the internal RC oscillator, then this is not needed.You can get away with putting the crystal on the breadboard too. In that case, there is no need to add extra capacitors, and it is wise to not use the I/O pins next to the crystal pins. Switching of those I/O lines will cause occasional lockups of the uC.Getting started with an atmega16 is pretty simple If you get a datasheet, the compiler package, and a programmer you've got most you need. I always liked the USBasp programmers. You can get them for a few EUR from china. "Official" programmers from Atmel have always been quite expensive. I almost bought a "Dragon" a long time ago, but it was not designed properly and it tended to fry itself when the USB voltage was low. I have not kept up with Atmel / Microchip after the merge. The atmega16 is very much like the atmega328. It mostly has more pins, and atmel can't settle on the peripherals, so timers and such may ave a few more or less configuration registers or bits.If you want to do something with the Microwilli, then you need an Eprom emulator. They are not so difficult to make yourself, but it requires a lot of wires because you have to buffer a lot of signals. With a few tricks you can reduce this: Use a RAM ic and then connect all the pins directly to a microcontroller (such as the ATMEGA16) Then you can program the uC pins to High-Z when the SAB .517 is running, but you also need something to keep the pins (both from the RAM chip, the hc573 and the SAB..517 in High-Z when your uC is loading data into the emulated eprom.

author: Doctorandus_P
author_rank: Super Contributor
timestamp: August 07, 2025, 06:20:55 pm
content: Quote from: Psi on August 07, 2025, 02:44:16 pmNo. There are series resistors on the USB data lines. And they seem to go to an SMT IC on the bottom of the board (Square on the top silkscreen). My guess is that this board is "arduino compatible".

author: Siwastaja
author_rank: Super Contributor
timestamp: August 07, 2025, 06:34:33 pm
content: If you like the layout of the LEDs and buttons on the ATMega16 board, then that could be quite usable for having some fun. The connector is very likely the standard 10-pin AVR in-system-programmer connector - see AVR programmers on Ebay/etc: AVRISP, USBTinyISP etc.It seems the board has female pin headers for every microcontroller pin which is highly valuable for playing around or connecting more stuff to it.

author: Psi
author_rank: Super Contributor
timestamp: August 07, 2025, 11:01:12 pm
content: Quote from: Doctorandus_P on August 07, 2025, 06:20:55 pmah, i can see the outline now. Yeah that is almost definitely a FTDI style chip.USB to Serial com port with Tx/Rx to the ATMega16.If it's a really old chip you may have issues with Win11/12 drivers, but hopefully it's fine. If you plug it in you should have a COM port appear in device manager.May/May not also need DC jack power. Its got a 5V regulator so probably ok with 9V or 12V. but you would first need to confirm the polarity. However it appears to have a diode.You cant program it over the USB port unless it has a bootloader on it.I guess you could get really lucky and find it's running arduino with the arduino bootloader already on it. Might be worth a try

author: amyk
author_rank: Super Contributor
timestamp: August 08, 2025, 01:32:45 am
content: First one looks like some sort of ancient Arduino.