6 ms·

PIC vs. AVR

64 points by gnosis 15y ago

swalberg 15y ago
The thing that got me into PICs was a generous sample program. You could sign up and get sent a few parts at no cost.
- phirephly 15y ago
  No cost, plus a $50 programmer. What is the PIC equivalent of the $20 USBtinyISP?
  - dkersten 15y ago
    I got a PICKit 2 on ebay for about $10.
  - swalberg 15y ago
    At the time there were many schematics available to program a PIC right off the serial or parallel port. I used one of those until I built a WISP628 which is an upgraded version of the idea.
flashingleds 15y ago
"PIC vs. AVR" means two different things depending on your context. The intelligent context is discussing which family best suits somebody new to microcontrollers (which thankfully is what this link is about). The moronic context is entrenched hobbyists arguing about why the family they chose is superior. Anybody who reads this headline and already understands what the acronyms mean is probably going to assume it's the latter.
Palomides 15y ago
for me, an architecture with a GCC port is a big selling point (between these two, that's AVR)
rcfox 15y ago
This article manages to mention just about every insignificant detail (who cares about the crappy IDEs they ship with?) and almost none of the actual properties of the chip! You would expect at the very least memory comparisons, clock speeds, and power consumptions. Maybe a mention of timers, ADCs, UARTs, etc.
- chamakits 15y ago
  I think it concentrated more on the aspects of how pleasant each is to use. The analysis was light on the technical side because ladyada targets more hobbyists (like myself :D ) and prototype creation rather than people that want to create a product that will be manufactured, reproduced and distributed on a large scale. Though I haven't used PIC personally though, I have used AVR before, and found it quite pleasant and flexible, though in all fairness I can't compare it to PIC. I will say though that there seems to be more resources and documentation on PIC than AVR (I bough a really good book on embedded devices that was based on PIC, and though the examples were helpful universally, they were targeting the PIC crowd specifically.)
- theatrus2 15y ago
  You'd think so.... I have no idea why the embedded world is so into what IDE they can use. Too many hardware engineers turned firmware engineers wanting an easy solution?
gamble 15y ago
ARM. Seriously, Cortex-M3 microcontrollers are much more powerful than any AVR or PIC at the same price, with roughly the same level of complexity as a high-end PIC/AVR. ARM already dominates high-end embedded systems, and is quickly penetrating the low end. Atmel and Microchip both see the writing on the wall; control of Atmel's ARM line was a major factor in Microchip's failed hostile takeover bid for Atmel several years ago. If you have any professional interest in embedded systems, it may be a better bet to invest time in ARM rather than an 8-bit architecture. There are a few arguments left in favor of PIC/AVR: ultra low power consumption, pin count, and price for the low-end chips, DIL package availability, and support for hobbyists in the forums. I'm not sure a difference of $1/unit and a few uW/MHz is relevant for hobbyists, and the Arduino is probably a better solution for people who aren't comfortable working with SMD. (Which honestly isn't that hard, anyway...)
- joshu 15y ago
  Can you link to some equivalent starter boards?
  - chintanp 15y ago
    One ARM based board which comes in my mind is BeagleBoard (http://beagleboard.org/ http://beagleboard.org/), its bit expensive 149$ but quite powerful.
    - miratrix 15y ago
      Something based on the Cortex-M series (http://www.sparkfun.com/products/10664 http://www.sparkfun.com/products/10664) probably is a better ARM starter board for someone who's getting started on the embedded stuff. Cortex-A series ARMs are completely different beasts in terms of complexity.
    - younata 15y ago
      I second that. The BeagleBoard is amazing. It can do real time (the original one can handle roughly 25 fps) computer vision, thanks to its built in DSP. The newer one should be even better (but I've not heard as much about it).
eck 15y ago
I've programmed both, though, not a PIC for many years now... PICs are just weird. The AVR is a pretty typical Harvard RISC: 32 registers, memory load/store, direct/indirect jumps, stack pointer pointing at ram, etc. It's still 8/16 bit, so some pairs of 8 bit registers work like 16 bit registers. The PIC has one accumulator register; ram is a set of (manually selected) register banks. Instructions operate on the accumulator and an operand in the selected bank. The stack is totally separate from other RAM, so it's fixed size (8 maybe?) and can only be used with call/return. I don't want to be judgmental; there's certainly some strange virtues to PIC, like the lack of any real state to save/restore on ISR entry/exit; but they really just don't fit my mental concept of a CPU. Exercise for the reader: Given the stack and register bank selection, which one of these has better C compilers? (Still, if you're learning something new, gamble is right: ARM is the future.)
- theatrus2 15y ago
  PIC is clearly designed for non-C assembly code, with all global variables. Its ancient. PIC32 is actually a MIPS core (sorta, kinda, maybe). It actually uses GCC to compile (good luck on compiling your own GCC though). However, there isn't much appeal with CM3 now on the scene.
- dkersten 15y ago
  PIC24, the 16bit PIC variant, is much imporved in this respect. You have 16 working registers (though one of these is used for the stack), four of these are shadowed for fast store/restore (eg, so the registers can be used in an interrupt handler), memory is directly accessible (most instructions can operate on both memory and registers equally) and the instruction set is very simple and regular. I have not used it with C (I have so far written my code in PIC assembly), but they claim the instruction set is very compiler friendly and at a guess, I'd say they're right since the memory access is very regular and most instructions also come in convenient three-operand forms. I'm not sure if the instruction set for the PIC24 is basically a 16bit variant of the PIC32 (have not looked into these in detail yet), but from the code samples I've seen, it seems to be. So PIC24, like PIC32, seems to be a RISC-based core. I actually like the PIC24. Besides the painful lack of (assembly) documentation outside the datasheet and various reference manuals (I guess nobody programs them in assembly these days? I suppose the same problem probably exists for other newish microcontorllers too?), it is very nice and easy to work with. The assembly language is very simple and easy to use. But, since the Cortex-M3 is similarly priced, but is faster (~100MHz vs 40MHz for a PIC24H), is 32bit, has a ton of features and peripheral support, its hard to choose PIC over these. I will probably look into switching to CM3 for my next project.
limmeau 15y ago
No mention of MSP430? Some of them come in DIL packaging (at least the little ones). The architecture has a GCC port and two free-as-in-small-glasses-of-beer commercial IDEs. The assembly language is bearable. The cheapest development board (with single-stepping debugger support) is $4.30.
- srik 15y ago
  Horrible mac dev support
- yardie 15y ago
  Have they sorted out the Mac support? I have one and haven't been able to get the toolchain to communicate with my MacPro. and no way am I booting into Linux just to push firmware.
- chrisjsmith 15y ago
  I'll second that - I have the same dev board I think if it's that really cheap TI one. Nice architecture and can run on ant farts for power. For those people who use a Mac, just fire up Parallels/Bootcamp and Windows - it works fine and won't kill you (honestly).
samic 15y ago
can someone please explain for me how is microcontrollers market? I mean does anyone of you make money out of it? how much? How does it help your job? thanks!
st3fan 15y ago
One thing that Lady Ada forgets to mention is that Microchip is working on MPLAB-X. A cross-platform version of their MPLAB IDE. I've used it on both Windows and OS X and it works well. It runs on Wind, OSX and Linux. This might be their way to get back into AVR territory. At least when it comes to hobbyists/makers.
asciilifeform 15y ago
PIC - because of its simplicity. On the PIC, I get the feeling of being "master of all I survey." The instruction set and system architecture fit in a magazine-sized booklet. The AVR, on the other hand, is a ball of goo, quite like the x86.
ladyada 15y ago
good god, i wrote this nearly -five- years ago please do not take it seriously at this point, its completely outdated
- eande 15y ago
  The time stamp from the webpage is "May 17, 2011 20:07"! But if it is outdated a PIC-AVR-ARM update would be interesting. Personally I used all three, but prefer nowadays PIC because of the wide-ranging PIC24&dsPIC and Microchips great stacks offering.
guan 15y ago
I know that a lot of people hate Arduinos, but I like the flexibility of prototyping on an Arduino, moving the same code to a raw ATmega328, and then (for teeny projects) maybe port to an ATtiny for cost and space savings.

PIC vs. AVR

64 points by gnosis 15y ago

swalberg 15y ago

The thing that got me into PICs was a generous sample program. You could sign up and get sent a few parts at no cost.

phirephly 15y ago
No cost, plus a $50 programmer. What is the PIC equivalent of the $20 USBtinyISP?
- dkersten 15y ago
  I got a PICKit 2 on ebay for about $10.
- swalberg 15y ago
  At the time there were many schematics available to program a PIC right off the serial or parallel port. I used one of those until I built a WISP628 which is an upgraded version of the idea.

flashingleds 15y ago

"PIC vs. AVR" means two different things depending on your context. The intelligent context is discussing which family best suits somebody new to microcontrollers (which thankfully is what this link is about). The moronic context is entrenched hobbyists arguing about why the family they chose is superior. Anybody who reads this headline and already understands what the acronyms mean is probably going to assume it's the latter.

Palomides 15y ago

for me, an architecture with a GCC port is a big selling point (between these two, that's AVR)

rcfox 15y ago

This article manages to mention just about every insignificant detail (who cares about the crappy IDEs they ship with?) and almost none of the actual properties of the chip! You would expect at the very least memory comparisons, clock speeds, and power consumptions. Maybe a mention of timers, ADCs, UARTs, etc.

chamakits 15y ago
I think it concentrated more on the aspects of how pleasant each is to use. The analysis was light on the technical side because ladyada targets more hobbyists (like myself :D ) and prototype creation rather than people that want to create a product that will be manufactured, reproduced and distributed on a large scale. Though I haven't used PIC personally though, I have used AVR before, and found it quite pleasant and flexible, though in all fairness I can't compare it to PIC. I will say though that there seems to be more resources and documentation on PIC than AVR (I bough a really good book on embedded devices that was based on PIC, and though the examples were helpful universally, they were targeting the PIC crowd specifically.)
theatrus2 15y ago
You'd think so.... I have no idea why the embedded world is so into what IDE they can use. Too many hardware engineers turned firmware engineers wanting an easy solution?

gamble 15y ago

ARM. Seriously, Cortex-M3 microcontrollers are much more powerful than any AVR or PIC at the same price, with roughly the same level of complexity as a high-end PIC/AVR. ARM already dominates high-end embedded systems, and is quickly penetrating the low end. Atmel and Microchip both see the writing on the wall; control of Atmel's ARM line was a major factor in Microchip's failed hostile takeover bid for Atmel several years ago. If you have any professional interest in embedded systems, it may be a better bet to invest time in ARM rather than an 8-bit architecture. There are a few arguments left in favor of PIC/AVR: ultra low power consumption, pin count, and price for the low-end chips, DIL package availability, and support for hobbyists in the forums. I'm not sure a difference of $1/unit and a few uW/MHz is relevant for hobbyists, and the Arduino is probably a better solution for people who aren't comfortable working with SMD. (Which honestly isn't that hard, anyway...)

joshu 15y ago
Can you link to some equivalent starter boards?
- chintanp 15y ago
  One ARM based board which comes in my mind is BeagleBoard (http://beagleboard.org/ http://beagleboard.org/), its bit expensive 149$ but quite powerful.
  - miratrix 15y ago
    Something based on the Cortex-M series (http://www.sparkfun.com/products/10664 http://www.sparkfun.com/products/10664) probably is a better ARM starter board for someone who's getting started on the embedded stuff. Cortex-A series ARMs are completely different beasts in terms of complexity.
  - younata 15y ago
    I second that. The BeagleBoard is amazing. It can do real time (the original one can handle roughly 25 fps) computer vision, thanks to its built in DSP. The newer one should be even better (but I've not heard as much about it).

eck 15y ago

I've programmed both, though, not a PIC for many years now... PICs are just weird. The AVR is a pretty typical Harvard RISC: 32 registers, memory load/store, direct/indirect jumps, stack pointer pointing at ram, etc. It's still 8/16 bit, so some pairs of 8 bit registers work like 16 bit registers. The PIC has one accumulator register; ram is a set of (manually selected) register banks. Instructions operate on the accumulator and an operand in the selected bank. The stack is totally separate from other RAM, so it's fixed size (8 maybe?) and can only be used with call/return. I don't want to be judgmental; there's certainly some strange virtues to PIC, like the lack of any real state to save/restore on ISR entry/exit; but they really just don't fit my mental concept of a CPU. Exercise for the reader: Given the stack and register bank selection, which one of these has better C compilers? (Still, if you're learning something new, gamble is right: ARM is the future.)

theatrus2 15y ago
PIC is clearly designed for non-C assembly code, with all global variables. Its ancient. PIC32 is actually a MIPS core (sorta, kinda, maybe). It actually uses GCC to compile (good luck on compiling your own GCC though). However, there isn't much appeal with CM3 now on the scene.
dkersten 15y ago
PIC24, the 16bit PIC variant, is much imporved in this respect. You have 16 working registers (though one of these is used for the stack), four of these are shadowed for fast store/restore (eg, so the registers can be used in an interrupt handler), memory is directly accessible (most instructions can operate on both memory and registers equally) and the instruction set is very simple and regular. I have not used it with C (I have so far written my code in PIC assembly), but they claim the instruction set is very compiler friendly and at a guess, I'd say they're right since the memory access is very regular and most instructions also come in convenient three-operand forms. I'm not sure if the instruction set for the PIC24 is basically a 16bit variant of the PIC32 (have not looked into these in detail yet), but from the code samples I've seen, it seems to be. So PIC24, like PIC32, seems to be a RISC-based core. I actually like the PIC24. Besides the painful lack of (assembly) documentation outside the datasheet and various reference manuals (I guess nobody programs them in assembly these days? I suppose the same problem probably exists for other newish microcontorllers too?), it is very nice and easy to work with. The assembly language is very simple and easy to use. But, since the Cortex-M3 is similarly priced, but is faster (~100MHz vs 40MHz for a PIC24H), is 32bit, has a ton of features and peripheral support, its hard to choose PIC over these. I will probably look into switching to CM3 for my next project.

limmeau 15y ago

No mention of MSP430? Some of them come in DIL packaging (at least the little ones). The architecture has a GCC port and two free-as-in-small-glasses-of-beer commercial IDEs. The assembly language is bearable. The cheapest development board (with single-stepping debugger support) is $4.30.

srik 15y ago
Horrible mac dev support
yardie 15y ago
Have they sorted out the Mac support? I have one and haven't been able to get the toolchain to communicate with my MacPro. and no way am I booting into Linux just to push firmware.
chrisjsmith 15y ago
I'll second that - I have the same dev board I think if it's that really cheap TI one. Nice architecture and can run on ant farts for power. For those people who use a Mac, just fire up Parallels/Bootcamp and Windows - it works fine and won't kill you (honestly).

samic 15y ago

can someone please explain for me how is microcontrollers market? I mean does anyone of you make money out of it? how much? How does it help your job? thanks!

st3fan 15y ago

One thing that Lady Ada forgets to mention is that Microchip is working on MPLAB-X. A cross-platform version of their MPLAB IDE. I've used it on both Windows and OS X and it works well. It runs on Wind, OSX and Linux. This might be their way to get back into AVR territory. At least when it comes to hobbyists/makers.

asciilifeform 15y ago

PIC - because of its simplicity. On the PIC, I get the feeling of being "master of all I survey." The instruction set and system architecture fit in a magazine-sized booklet. The AVR, on the other hand, is a ball of goo, quite like the x86.

ladyada 15y ago

good god, i wrote this nearly -five- years ago please do not take it seriously at this point, its completely outdated

eande 15y ago
The time stamp from the webpage is "May 17, 2011 20:07"! But if it is outdated a PIC-AVR-ARM update would be interesting. Personally I used all three, but prefer nowadays PIC because of the wide-ranging PIC24&dsPIC and Microchips great stacks offering.

guan 15y ago

I know that a lot of people hate Arduinos, but I like the flexibility of prototyping on an Arduino, moving the same code to a raw ATmega328, and then (for teeny projects) maybe port to an ATtiny for cost and space savings.