An old thread, which is better PIC or AVR never compare the 18F or higher PICs

[blueroomelectronics]

Here's a link to an article on PIC vs AVR
https://www.electricstuff.co.uk/picvsavr.html

I don't know much about AVRs but the comparison is valid for the 16F series PICs vs AVR

What needs to be added are the newer high end PICs and AVRs

 

[Sceadwian]

AVR's now have a single instruction I/O pin toggle ability on later production models. Older AVR's had to read the port state, Xor the bits and output it again.

Configuring AVR reset pin as I/O disables in-circuit programming. On PICs the reset pin can be configured as an input without disabling serial programming, provided whatever is connected to it allows for the 12.5v programming voltage.

That however is blatantly wrong. AVR's are able to be reprogrammed in the same way (high voltage programming) asuming of course the connected circuitry allows for it. Units such as the 8pin Tiny AVR series chips don't have the ability to parallel reprogram so they only available option is serial programming. I think the high voltage and serial ISP protocols are slightly different but I've never studied them as my STK500 does the work for me.

I also think the clock advantages are understated on AVR's. The AVR's are 1 instruction per clock period, that's it. That means optimized I/O code for an AVR can run up to 4 times faster for burst transfers than a PIC. That's nothing to cough at. As well as the tiny15's high speed PLL which allows up to 12.8mhz (square wave 50/50 duty only) signals to be generated from a 1.6mhz internal oscilator.

The tiny25/45/85 can actually be run off of the PLL ouput allowing an incredibly input/ouput flexibility with the clock. It also has an onboard temperature sensor and the ADC allows a voltage divider to feed back VCC to possibly temperature/voltage compensate the internal R/C

Anyone wanna chime in on the PIC side?

 

[Nigel Goodwin]

Anyone wanna chime in on the PIC side?

As for clock speed, the 18F series are also 1 instruction per clock cycle, using a similar PLL technique.

There's nothing much between them, and there's already LOT'S of comparisons on the net. Personal choice, choose which you prefer, or something else entirely?.

 

[cadstarsucks]

Here's a link to an article on PIC vs AVR
https://www.electricstuff.co.uk/picvsavr.html

I don't know much about AVRs but the comparison is valid for the 16F series PICs vs AVR

What needs to be added are the newer high end PICs and AVRs

Take a look at the Luminary ARMs, they compare favorably performance per dollar.

D.

 

[Mike - K8LH]

Is Luminary a particular model or type of ARM?

 

[3v0]

Take a look at the Luminary ARMs, they compare favorably performance per dollar.
D.

Mouser has several Luminary's in the LQFP-48 package.

Is found the ARM Cortex M3 microcontroller development board for $50. This is sort of neat in that you can use it as a target or an JTAG adaptor (ICD).

What hardware and software tools do you use ?

 

[evandude]

Mouser has several Luminary's in the LQFP-48 package.

Is found the ARM Cortex M3 microcontroller development board for $50. This is sort of neat in that you can use it as a target or an JTAG adaptor (ICD).

What hardware and software tools do you use ?

That looks like a VERY cool board. even has an OLED display on it!

I guess my main question would be if the JTAG interface works with all ARMs, or if it only works with the Stellaris ones? It says on the Luminary product page "In-Circuit Debug Interface (ICDI) for any Stellaris microcontroller-based target board" For the price, it sounds like a GREAT starter package as long as the JTAG is universally compatible (software- and hardware-wise).

 

[3v0]

That looks like a VERY cool board. even has an OLED display on it!

I guess my main question would be if the JTAG interface works with all ARMs, or if it only works with the Stellaris ones? It says on the Luminary product page "In-Circuit Debug Interface (ICDI) for any Stellaris microcontroller-based target board" For the price, it sounds like a GREAT starter package as long as the JTAG is universally compatible (software- and hardware-wise).

IIRC someone posted that there is no one tool that covers all ARMs. Microchip has spoiled up by providing the ICD2 OS's required by all of its chips.

3v0

EDIT:
Before some one chew on me.

JTAG hardware is somewhat generic. The software that uses it to talk to the monitor on the target chip is not. HP made a device called a software probe to debug JTAG chips. You reflashed it to work with a specific processor. This is much like the ICD2 does.

 

[Blueteeth]

Hi,

I have noticed a sudden drop in prices or certain new development boards from atmel. I mean,. the 'Dragon' board is available, in the UK, for 35UKP. And it's pretty damn powerful. Unfortunately....as cheap (and COOL!) as these high-end ARM micro's are, right now I don't have any applications for them. I'm still at the 'leds, LCD's and switches are a novelty' stage

I will say one thing. I've been meaning to get into AVR's for a while now, purely for the similarities...whilst everyone points out the differences, its not that hard at all to change horses. I just brought a programmer from ebay (serial £3), an atmega88 (£1.12) and made my own mini dev board. This was really just for one reason.....the double buffered USART. As far as I can tell, its the cheapest way to 'stream' bits for RF comms, with minimum CPU overhead. I don't know why the 'AVR USB' software bitbangs, when the USART is quite capable of sending bytes back to back with no gap inbetween and virtually any speed (in SPI mode). Apparently it also has an internal 'debug' module. I haven't used that yet, but schematics for JTAG/ISP interfaces are everywhere on the web. And add a cheap (£4?) USB->serial bridge from ebay, and you've got a USB development system for it.

I'm still learning though, done the obligitory 'blinky' program, in both assembly and C, so now I'm just building up my own library of code...its just getting used to the extra instructions..using them where appropriate to replace what would have been several PIC instructions.

Gah, I haven't even started on 18F series yet...but thats why I'm getting a PIC dev board made up (all 18pin+ DIL PIC's).

Sorry if this isn't really on topic, but I just wanted to say that I don't think the differences aren't really all that...except maybe value for money. I'll continue to use both I think, at least for hobbyist projects. I'll post pic's of all three dev boards one day, once they're all finished.

Blueteeth

 

[Sceadwian]

CadStar: The reason PIC's and AVR's are used by hobbiest more than ARM is because to the best of my knowledge there are no ARM processors that come in DIP packages, which makes quick and easy breadboarding impossible without some kind of daughtercard setup which raises the total cost considerably over cheap PIC's and AVR's. 99% of hobby users don't need the kind of speed and processing power an ARM has either. They're really not in the same catagory.

 

[cadstarsucks]

Is Luminary a particular model or type of ARM?

Luminary is a company that ARM started to produce their cortex core in silicon. All their normal customers had invested so heavily making microcontrolers in the ARM7 core that none were interested in the cortex core which was designed specifically for microcontrolers.

D.

 

[cadstarsucks]

Mouser has several Luminary's in the LQFP-48 package.

Is found the ARM Cortex M3 microcontroller development board for $50. This is sort of neat in that you can use it as a target or an JTAG adaptor (ICD).

What hardware and software tools do you use ?

They have an LM3S101 that is in an SO28, quite a bit easier to handle, for $2.20. You can D/L serial programmer software from Luminary's site. I am led to believe that the Kiel tool set (a visual debugger and c compiler) are free for up 32K of program, for a CD request at their site.

D.

 

[cadstarsucks]

That looks like a VERY cool board. even has an OLED display on it!

I guess my main question would be if the JTAG interface works with all ARMs, or if it only works with the Stellaris ones? It says on the Luminary product page "In-Circuit Debug Interface (ICDI) for any Stellaris microcontroller-based target board" For the price, it sounds like a GREAT starter package as long as the JTAG is universally compatible (software- and hardware-wise).

JTAG is the standard debugger interface on the ARM core. The ICDI is specific to the cortex cores. Serial port programming is vendor specific firmware. At work we currently use an Atmel AT91R40008 that we debug and program 2.3M through JTAG and a NXP LPC2134 that we program 115K through RS232.

It is a nice little starter, we were comped one at work. It comes with a serial interface cable and the Kiel tools CD ( which has 6 different RTOSs on it as well )

D.

 

[cadstarsucks]

IIRC someone posted that there is no one tool that covers all ARMs. Microchip has spoiled up by providing the ICD2 OS's required by all of its chips.

3v0

EDIT:
Before some one chew on me.

Ooh I will, I will, pick me! pick me!
Most ARM tools cover all ARMs that is what is nice about them. What may or may not be there are the specific stuff hung off of the core. All will support the ARM IT cores but you might have to enter some of the other bits and bobs, register models for A/Ds or interrupt controllers that the silicon house put in.

The core is the core, be it ARM, THUMB, THUMB2, I think jazzele is their hardware java engine.

ARM with extensions is the main instruction set. THUMB created an assembly compatible subset that is compressed into a 16 bit instruction, THUMB2 eliminated the need for ARM instructions at the lowest level and extended THUMB with some 32 bit instructions. And Java is, well, Java.

D.

 

[cadstarsucks]

CadStar: The reason PIC's and AVR's are used by hobbiest more than ARM is because to the best of my knowledge there are no ARM processors that come in DIP packages, which makes quick and easy breadboarding impossible without some kind of daughtercard setup which raises the total cost considerably over cheap PIC's and AVR's. 99% of hobby users don't need the kind of speed and processing power an ARM has either. They're really not in the same catagory.

That is a bit of a nuisance for a hobbyist Wow what a rip off those adapters are! If anyone wants one I can generate artwork to convert them to DIP spacing so you can solder pins and ANY ICs on. Then you can print it out on a laser copier or printer and transfer the toner for a PCB.

D.

 

[Blueteeth]

With regard to 'adapters', one could try the 'dead bug' style. Or at least buying a cheap fr4 protoboard, with one pad per pin (for 'standard' pitch) and gluing the chip to the non-copper side, then just using thin wirewrap/enamelled wire to connect pins. Bit of a ***** for 44 pins+ but its doable, and surprisingly reliable. I've also made adapters from plain copper clad, cutting with a knife (I know) and a ruler to create' tracks' that are easier to solder to than the pins themselves.

After all that hassle I probably sohuld have etched a board, but hey, it works.

 

[3v0]

Ooh I will, I will, pick me! pick me!
Most ARM tools cover all ARMs that is what is nice about them. What may or may not be there are the specific stuff hung off of the core. All will support the ARM IT cores but you might have to enter some of the other bits and bobs, register models for A/Ds or interrupt controllers that the silicon house put in.

The core is the core, be it ARM, THUMB, THUMB2, I think jazzele is their hardware java engine.

ARM with extensions is the main instruction set. THUMB created an assembly compatible subset that is compressed into a 16 bit instruction, THUMB2 eliminated the need for ARM instructions at the lowest level and extended THUMB with some 32 bit instructions. And Java is, well, Java.

D.

Thank you for that. in regard to the toolset. The ARM licensees do not coordinate to make the "ARM" as easy to use as a PIC. If they did you would not have to bodge in the missing bits. A bit ugly but not a show stopper in that it only has to be done once per processor. In most cases someone else will have been there first.

I like what the ARM people have done. It is good stuff. Do you remember the Pascal P machine.

If I got it right "the ARM good stuff" exists at a level above the $10 dollar (maybe $5) and under processors that most of us are using. It still floors me that the PIC18F2550 is less then $6.

In the end I do not much care about who makes the processor. I use a high level language to insulate me from the nuts and bolts of the instruction set. For me the quality of the toolchain is more important then the processor itself.

After I retired I did not touch a microprocessor for 5 years. This summer I wanted to automate and monitor my greenhouse. I started with the PICs not because of the great chip that it is/is-not but because the toolchain was very affordable. I started with the eval version of the CCS compiler and the Tiny-ICD2. Total cost under $100 including a few PICs.

3v0

 

[cadstarsucks]

Thank you for that. in regard to the toolset. The ARM licensees do not coordinate to make the "ARM" as easy to use as a PIC. If they did you would not have to bodge in the missing bits. A bit ugly but not a show stopper in that it only has to be done once per processor. In most cases someone else will have been there first.

I like what the ARM people have done. It is good stuff. Do you remember the Pascal P machine.

You're welcome Yes almost always. Often even by the silicon maker. Can't say that I do...

If I got it right "the ARM good stuff" exists at a level above the $10 dollar (maybe $5) and under processors that most of us are using. It still floors me that the PIC18F2550 is less then $6.

Could you define "good stuff" in this context? Off hand I am only finding that for a 1600 piece reel. Are you using that one for comparison because of the USB?
[/QUOTE]
In the end I do not much care about who makes the processor. I use a high level language to insulate me from the nuts and bolts of the instruction set. For me the quality of the toolchain is more important then the processor itself.

After I retired I did not touch a microprocessor for 5 years. This summer I wanted to automate and monitor my greenhouse. I started with the PICs not because of the great chip that it is/is-not but because the toolchain was very affordable. I started with the eval version of the CCS compiler and the Tiny-ICD2. Total cost under $100 including a few PICs.

3v0[/QUOTE]
I know that for most hobbyists small scale economics and comfort are priorities. Sometimes comfort outweighs economics, but in the case of many I would suspect not...

D.

 

[3v0]

Could you define "good stuff" in this context? Off hand I am only finding that for a 1600 piece reel. Are you using that one for comparison because of the USB?

The thing that caught my eye was the strongArm.

At that price the USb is a freebee. I is a 48mhz 23mb chip.
newark part number 80K6054
MICROCHIP PIC18F2550-I/SP
1 Each $5.92


Goto run. Will continue latter.

 

[3v0]

I know that for most hobbyists small scale economics and comfort are priorities. Sometimes comfort outweighs economics, but in the case of many I would suspect not...

D.

I am not sure what I wrote that led you to say this ? My point was that the PIC gave me a reasonable level of both.

3v0