PIC Developer boards questions - Page 1
Forum section: electronics / general

author: pullin-gs
author_rank: Regular Contributor
timestamp: May 17, 2012, 05:06:37 pm
content: I'd like to play around a bit with micro controllers (PIC variants).What on-line resources or forums are there with good developer-board discussions?I think a developer board is a good way for me to get started quickly (I'm lazy).Ive narrowed it down to two: An EasyPic board or the QL200 board.I like the cost and "included" hardware features of the QL200....I'd go with that one but am concerned the vendor does not support a "command line" interface to the board.Can someone quantify what this means in terms using the board and downloading code?What are some other differentiators between EasyPic and QL200 that I should be considering?PS: My background.70's- scratch-built tube and transistor stuff (scavenged parts off old TV chassis throw-aways)80's - EE Education which got me introduced to linear, logic chips, and microprocessors.Late 80's - Two year stint as a Z80, x86 programmer (wrote a one-pass assembler also).From 1990-today...on-again and off-again hobbiest with tons of discrete components and lab.

author: Unknown
author_rank: Unknown
timestamp: May 17, 2012, 05:34:13 pm
content: I would get something supported by MPLAB, not just by some random proprietary environment. This usually limits you to Microchip programmers or clones of them (not recommended). Microchip programmers are also widely supported in third-party development environments. What's wrong with connecting a PICkit to a development board? If you do get some third-party programmer, make sure it supports recent PICs, not just some ancient PIC16 devices.

author: caroper
author_rank: Regular Contributor
timestamp: May 17, 2012, 09:31:13 pm
content: If don't have any particular chip in mind and you have a Lab and experience, I am about to publish a QuickStart guide to the PIC32MX150 on a Breadboard.I would have posted it yesterday but I needed to work out how to embed the graphics into the post and what the max post length can be.I will try and get the first few post up tomorrow for you to look at.

author: pullin-gs
author_rank: Regular Contributor
timestamp: May 17, 2012, 09:57:56 pm
content: Very good.I'll definitely read it over.I'll want to start out with one of the smaller 8-bit PIC microcontrollers though.Are the instruction sets and assembler syntax the same on all PIC variants?Come to think of it, I'm too old for assembler work....is there a common-PIC-platform open-source compiler or developer environment?I do have a nice breadboard w/power with integrated power+clock+switches, and a nice assortment of CMOS chips (logic, LED drivers, counters, etc.). I could do quite alot with just that I imagine.I do not have a PIC programmer though.

author: Unknown
author_rank: Unknown
timestamp: May 17, 2012, 10:13:53 pm
content: There is no good open-source compiler for the 8-bit PICs (the only option is SDCC) as far as I know. Both the MPLAB compiler for the 16-bit and 32-bit PICs are based on GCC, however. Getting C30 or PIC32 GCC to work with IDEs like Code::Blocks or Eclipse should be fairly straightforward. Not sure about debugging capabilities.Microchip's MPLAB (X) is free and includes C compilers for 8-bit, 16-bit and 32-bit parts, no optimization after the first week or so though.

author: caroper
author_rank: Regular Contributor
timestamp: May 17, 2012, 10:28:41 pm
content: Quote from: pullin-gs on May 17, 2012, 09:57:56 pmI wouldn't if I were youThe 8bit chips are harder to use than the more modern chips.Quotewithin reason, yes, until you get to the high end chips like the DSP-PIC and the one I want to talk about as that has a MIPS Core.QuoteCommon and Free but not Open-source.MPLAB, but it is the best tool for working with PIC processors.And I agree on the assembler too. I only ever used the Assembler until I started working with the PIC32 family and C32. It is a very good language and generally spits out code that is more efficient than I could do in Assembler.QuoteRather than spending money on a development kit spend it on a good programmer.I have several development boards and they are a wast of money after the first few weeks, where as a good programmer will last you for ages and program the entire family of chips.I have the PICkit2, PICkit3 and ICD3, the Explorer16 and the PIC32 StarterKit, both with onboard programmers.I seam to collect PIC programmers like Dave Collects MultimetersThe PICkit3 is the cheaper one but if you can afford it the ICD3 is well worth the money.Both do some debugging but the ICD3 is lightening fast.You may be able to get the PICkit3 with a bundled starter board and chips, have a look at the Microchip web site.CheersChris

author: caroper
author_rank: Regular Contributor
timestamp: May 17, 2012, 10:54:05 pm
content: Another thought, and one that I may well be shot down for, but have you looked at the chipKit Boards?They are PIC32 based with an Arduino Form factor and use an open-source IDE and compiler.They don't need a programmer as they run with a bootloader, but they can be used with a PIC programmer as a Development board along with MPLAB, that is the way I have been using them.If you are just getting back into the processor world it may be a good place to start.It can run all of the basic Arduino Sketches, has far more processing power and I/O capability, and you are not locked into the Arduino world.You can use it to learn C (The compiler and libraries are C++ but they will compile native C code too) and then move on to MPLAB and the whole family of chips when you are ready.Of all the boards in My collection the ChipKit Uno is the only one within permanent reach on my desk.I use it to test hardware or software concepts before merging it into code on production boards.CheersChris

author: nctnico
author_rank: Super Contributor
timestamp: May 18, 2012, 12:41:13 am
content: Note this thread:https://www.eevblog.com/forum/microcontrollers/pic32mx-quickstart/Having a jumpstart helps a lot.

author: pullin-gs
author_rank: Regular Contributor
timestamp: May 23, 2012, 12:36:13 pm
content: I went ahead and bought the QL200 for $125 shipped.I also expanded my inventory of 4xxx chips.....first project is a digital clock (7-segment display)....next project is a clock using LEDs as "hands".After I get the logic-chip 4xxx playing out of my system I'll plunge into the PIC projects and build the same clocks.Cant wait for it all to arrive. I'm spending way too much time on the internet....need to get to building stuff instead!PS: Is there such a thing as a COTS x-tal clock source will get me 1-second interval pulses? Or am I gonna have to build it?PSS: I was able to get my chips (including counters, disp drivers, and some other CD4xxx stuff) for .22c to .35c.....almost half off of electronics goldmine and other "street-price" sites we all use. I stocked up.

author: poorchava
author_rank: Super Contributor
timestamp: May 23, 2012, 04:06:02 pm
content: I'd recommend to buy a chip, design the pcb for it and generalyl do all the stuff by your self (as opposed to buying development board). This way you're going to learn hardware aspects of microcontroller implementations, which you will probably have to learn at some point anyway n order to design a device utilizing a microcontroller.

author: T4P
author_rank: Super Contributor
timestamp: May 23, 2012, 04:34:58 pm
content: Quote from: poorchava on May 23, 2012, 04:06:02 pmYes, this was exactly what i had in mind about learning a microcontroller's hardware side

author: nctnico
author_rank: Super Contributor
timestamp: May 23, 2012, 06:03:27 pm
content: Quote from: poorchava on May 23, 2012, 04:06:02 pmI like that too. It gives you the opportunity to put whatever you want on the board and leave off everything you don't need. I do like to look at diagrams of evaluation boards to see if I can spot a good idea.

author: pullin-gs
author_rank: Regular Contributor
timestamp: May 23, 2012, 07:29:45 pm
content: Quote from: poorchava on May 23, 2012, 04:06:02 pmI like the idea of breadboarding first (be it with a design aid or not), finalizing on the components, and THEN putting it to a board. No point in designing/debugging on a custom board only to discover you left something out.Mocking up the circuit is the only way to go to ensure your vision is implemented in the end without a birds-nest of wire-jumpers to wire in the traces you missed.

author: nctnico
author_rank: Super Contributor
timestamp: May 23, 2012, 08:52:04 pm
content: If you make the PCB debug friendly then it is much easier to change something. Breadboards have a habbit of falling apart. For some circuits I etch a board first to try the basics. Some prototypes end up with several sub-boards.Some of my stone-age designs:http://nico.adresboekje.nl/PRINTJE.jpgIts a frequency counter build from LS-TTL chips.http://nico.adresboekje.nl/PROTO.jpgThe PCB on the left is a clock circuit I cut from an old motherboard. I needed a 100MHz clock... This project's end result is my 'avatar' picture BTW.

author: xquercus
author_rank: Contributor
timestamp: May 25, 2012, 01:02:26 am
content: QuoteA lot of people will say to skip the PIC16Fs (midrange 8-bits). If you are interested in assembly language, these chips are so simple that I think its a great platform to cut your teeth on. If this interests you, you can pick up a PICKit 2 which comes with a low pin count demo board, a PIC16F chip, and an assembly language tutorial. It's less than $50. The only downside is that the PK2 will not program a few of the newer PICs. The majority of code examples out there for the 16F family are in assembly so it's easy to find lessons. Spending time with assembly is a good way to get you familiar with the hardware which can be useful when you transition to C.If you want to do C, don't bother with the 16F or lesser lines. If you are determined to go 8-bit, go with the 18F line.QuoteI'm only familiar with the 8 and 16-bit PICs. The instruction set and architecture are quite similar but not the same. The 32-bit devices use MIPS so I imagine they are quite different.I know you said you wanted to go with a development board but if you change your mind, I really enjoy playing with PICs in DIP packages on a bread board. There is a fairly good PDF which covers rolling your own development board with a breadboard here:http://www.ece.msstate.edu/courses/ece3724/main_pic24/labs/board_walkthru_pic24.pdfThat would pretty much get you set up to explore "Programming 16-bit Microcontrollers in C" by Lucio Di Jasio. Also, if you go 8-bit, "Applying PIC18 Microcontrollers" by Brey is quite good. These books use the C18 and C30 compilers.

author: poorchava
author_rank: Super Contributor
timestamp: May 25, 2012, 12:16:33 pm
content: My opinion remains still the same on MCU's (no intention to start flame war ). For a starter and for 8 bit stuff get AVR. IMO they are far superior than pic16 and pic18. They have less complicated architecture and are easier to program in ASM as well as C. programmer for those consists of one 74hct244 logic chip and an lpt connector + few resistors (no affordable debugger though).I'd say that only case when it's wise to buy development board are FPGA chips. Almost all of them come in OMG-WTF-BGA/CSP/LGA packages which require multilayer pcb with a clever design. And getting 1 piece of custom 4 layer pcb (not to mention 6 or 8 layer ones) costs a TON of money. Plus they require config memory, levelshifters, often some sophisticated power supplies etc.As for homemade stuff it's completly possible to fabricate board with ghetto methods like toner transfer with 8/8 trace/clearance (better stick to 10/10). Soldering everything 0.5mm pitch QFPs, TTOPS and 0603 easy (0402 are kinda bitch though and i generally don't use those). Larger stuff like 0.05" pitch SOIC, 0805, 1206 and such you could solder even with drainpipe welding torch. In most cases there's no need to buy a ready made board, especially that Microchip is nice enough to provide free samples to private people (given you don't abuse this service).Example cost of simple eval-board:-pic of your choice - free-single sided copper clad laminate - $5 for A4 sheet?-max232+db9 connector = $1-2 (for debug/data-dump/comms)-voltage regulator - $0.3? (meaning 7805 or 78033)-100n caps, resistors, leds etc in 0805 case: like $0.5 for 100pcs-crystal - $0.4-pin headers - about $0.5 for 40-50 unit stripAnything else you can assemble on universal board of breadboard or do it spider-style (at least that's direct translation from polish - meaning parts soldered lead-to-lead without pcb).

author: pullin-gs
author_rank: Regular Contributor
timestamp: June 05, 2012, 04:28:58 pm
content: Quote from: pullin-gs on May 23, 2012, 12:36:13 pmSuccess!I got my board about a week ago and went straight to work.I'll post a review on it as I settle in on my selected work environment and after I compile the list of on-line resources I used.So far I have done the basic led, switch, display, clock, and created a few "composite" programs of these code pieces. My latest project of my own is a looped main routine, interrupted by key-press (4x4 matrix), choosing led combinations based on table lookup keyed off register content resulting from key-press, and then displaying LEDs.In a nutshell:1)Got the MCU bug less than two months ago. I knew ZERO about microcontrollers, but have a very good foundation in assembly (Z80, x86).2)Discovered development board options, choose QL200 and bought stuff.3)Settled on a PIC16F (Thanks forum!).4)Built my PIC development lab (bolted everything down inside a Halliburton "ZERO" case).5)Loaded up the QL200 application and USB driver....verified connectivity OK.6)My studies up to this point suggested I go assembler route for now. Will reassess after I fully understand internal PIC16F operation in managing I/O flow, clocking, and interrupt handling.7)Settled on MPLAB, MSAM assembler, and MPLAB-SIM for debugging (need a debugger/programmer....looking for input to guide my selection).8)Studied PIC16F syntax, PIC16F "include" library.9)Was creating my own code within a day.....I had no idea how quickly my assembler knowledge from TWENTY-THREE years ago would come back to me. I was expecting this to take a month or more.Why the development board was a good choice for me:It allowed me to jump straight into creating code. I did not have to patch a single jumper. Everything is routed via dip switches, uploading code through the simple USB programmer.It kick-started my learning process by a few weeks. I expect I will be putting my old breadboard trainer to work very shortly, relegating the QL200 for basic stuff such as programming the MCU, keyboard, switches, LEDs, the onboard clock, etc.