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Need help on GPIO registers

goswamiarindam
Associate II
Posted on May 09, 2008 at 13:04

Need help on GPIO registers

5 REPLIES 5
goswamiarindam
Associate II
Posted on May 17, 2011 at 12:26

Hi,

STM32F103 is the first 32 bitter I am working on.. Can you guide me to online resources, which specify how GPIO port control registers are mapped, and their functions

[ This message was edited by: goswamiarindam on 08-05-2008 13:28 ]

goswamiarindam
Associate II
Posted on May 17, 2011 at 12:26

I have found the information on how GPIOs are mapped ... Can someone help me with information on how the control registers for GPIO work ... I am at sea here ..

I do not seek a detailed explanation on this forum ... But if you could paste a link here that gives me the info, that would help me a lot

paulsmitton9
Associate II
Posted on May 17, 2011 at 12:26

I'm assuming you have the 'Reference Manual' (which details GPIO registers).

Try downloading the Firmware Library, and look at the two GPIO examples.

This will make it easier to use GPIO if the reference manual isn't much help.

Both are at:

http://www.st.com/mcu/familiesdocs-110.html

goswamiarindam
Associate II
Posted on May 17, 2011 at 12:26

Thanks Paul,

The code helped.

jj
Associate II
Posted on May 17, 2011 at 12:26

Here's some more ''first ARM'' guidance:

If you're like us - you will be struck by the seeming complexity,

number and length of the signal/register definitions/declarations. Compared to your familiar 8-bit - the ARM is off-putting. Like you -

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''Opens the power, flexibility and performance of these GREAT, new micros!

And once you go thru the required ''set-ups'' and definitions you will

be able to re-use most. So it is primarily a ''one-time'' learning

curve battle. Truth in Advertising - as your focus shifts beyond I/O

you will AGAIN have to master pin, signal and register definitions.

All of the flexibility causes an ''apparent'' significant increase in

set-up/mode-selection etc.

Here are some specific recommendations my firm employs:

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the ''other guy'' often proves helpful. Too often - engineers ''Lone Ranger'' mentality retards their learning and career achievements.

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a path more destined to failure/frustration! KNOW what you're doing with the hardware OR software AND be sure of your smt production skills BEFORE attempting your own pcb design... Engineers/Programmers MUST value their TIME !

This forum is filled with talented, generous contributors. You should

cover the ''basics'' before posting - provide complete data - and always

''close the loop'' so that our forum community LEARNS what worked/failed.

blatant ''plug'' follows:

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