STM32 and PIC32

Posted on May 07, 2012 at 11:14

Hello,

Honnestly, it took me a few months to get the ST USB stack to work correctly (and still not perfectly ...).

I used to work with Microchip before ... I like STM32's processing power, bunch of peripherals, etc ... but the I2C is crap, the USB stack is buggy like nothing else, plus the need for commercial dev tools (I'm using TASKING for ARM).

If you need to dev fast, don't care too much about the MCU price in the final design, and/or don't want to spend money on new tools, go for the PIC32.

I went to STM32 initialy because of the lack of PWM inputs/outputs on the STM32 (needed at least 10).

Thomas.

Posted on May 07, 2012 at 12:23

''I  have a new project with short deadtime (sic?) to finish''

I presume you mean, ''deadline''?

So, if time-to-complete is your key issue, then that nust be a (the?) key criterion in your microcontroller selection.

''microchip is giving a complete working library''

 

That's the advantage (to the chip manufacturer) of having a proprietary architecture: it means that they know you are locked-in, because the stuff cannot be (directly) used on any competitor's products!

''i could not find any free library like the one in microchip for STM32''

Because STM32 uses an industry-standard architecture (Cortex-M3), there would be no way for ST to prevent such a library from being used on competitor's Cortex-M3 products.

On the other hand, because Cortex-M3 is  an industry-standard architecture, there is a very wide range of libraries - both ''free'' (sic) and commercial - available for it...

ST also have a number of  ''special arrangements'' with commercial stack vendors; eg, the InterNiche Nichelite  TCP/IP stack...

''To be honest I would like to use STM32''

 

Why, specifically? Particularly in relation to your project goals & constraints...

''PIC32 is forcing me to use it''

You have stated a very strong reason for using PIC32 - so what is/are the reason(s) against?

 

Posted on May 07, 2012 at 15:30

ST has already USB Host library demo with Mass-Storage and FAT file system

Search for UM1021 for STM32F105xx, STM32F107xx, STM32F2xx and STM32F4xx USB On-The-Go host and device library

Posted on May 07, 2012 at 15:49

 I like STM32's processing power, bunch of peripherals, etc ... but the I2C is crap, the USB stack is buggy like nothing else, plus the need for commercial dev tools (I'm using TASKING for ARM).

1) ''STM32'' is incomplete the I²C problems are stm32F1xx only.

2) the PIC is by no means error free

3) the price you pay for using industry standard processors with all the advantages coming from that and, you have choice based on the tool you like best not  being forced to the one end only 'matching' tool.

Erik

Posted on May 07, 2012 at 16:19

''the need (sic?) for commercial dev tools''

 

 

What do you mean by that?

Posted on May 07, 2012 at 18:10

@Erik : sorry I'm working on STM32F205 and I2C is realy CRAP, so it's not only STM32F1.

And MPLAB X is a quiet good tool ... which is basically free (of course because it works only with microchip proucts).

Keil, TASKING, etc are all above 1k€ licence fee (some far above), and it's true, there are free tools ... but he mentionned short dev time, so free tools are not an option.

Thomas.

Posted on May 07, 2012 at 18:28

''he mentionned short dev time, so free tools are not an option.''

 

He also says he's been using STM32 for 2 years - so he should be OK with his tools by now!

On the same basis, should he be looking at ''free'' (sic) libraries/stacks at all...? 

Posted on May 08, 2012 at 03:19

''... but the I2C is crap, the USB stack is buggy like nothing else, ''

I have been using I2C AN2824-Optimised example firmware on STM32F, it works for me without problems. Similarly i used the same firmware on STM32L...works fine !

The USB library is also under use, i understood they are already usb.org certified, it works fine for me..

Posted on May 08, 2012 at 08:29

Thank you all ;

first i could not find UM1021. please could you give a link?

Till now I dont have any problem with STM32 ; it ok for me ; also PIC32 is a good device.

what i liked in microchip that the documentaion is better than the ones for ST; I have playing with PIC32 for just a months and I found that i have more free libraries more that of STM32  and all of them are bug free working from the first play  ( USB host ; file system ;ethernet  ; USB printer interface ... etc) ; even a full version keil does not have those libraries; The only thing that make me use stm32 now is the industry standarts .

However 90% I  will go with PIC32 ; but i will  have a deep thinking time to deside; because i need also EMC test for our boards I think STM32 is better in this case.

If you have anything to add ; please add it .

Regards

Posted on May 08, 2012 at 12:00

http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/USER_MANUAL/CD00289278.pdf