I have a STM32F4Discovery development board and have been getting
comfortable enough with  ARM processors to start considering a serious
project. In preparation for that, I recently ordered a bunch of ST
micros and a ST-Link programmer.

My development board works great. However, I built two hand-wired
prototypes with the 20 and 32 pin version of the STM32F030 and I found
I was unable to program them. I read ST's "getting  started"
application note [1] could not find anything with my prototypes that
would cause an issue.

Here's the issue I'm running into :
* I cannot program my hand wired prototypes
-> I tried using my st-link programmer
-> I tried using the on board st-link programmer on my STM32F4Discovery
-> I probed the clock and data signals on my scope; they look clean
-> I tried different computers and programming software. (ST's utility
and an open source utility which works well for my development board)

Modifications I tried:
-> I added decoupling capacitors to my prototypes (supply and reset pin)
-> I tried external pull-up / pull-down resistors.
-> I tried holding the device in reset
-> I tried booting the micros into system boot loader mode
-> I tired swapping the clock and data pins
-> I tried with and without the reset pin connected
-> I tried with an external power supply
-> I tried adding a resistor (tried 50, 330, 1k) in line with the
programmer's clock line in order to reduce ringing

I decided I would check my standalone ST-link to see if it was
functional. I wired it up to my STM32F4Dicovery board and found that
it also would not program it. But! I can see the clock and data
reaching the right pins on my scope.

This baffles me, since the STM32F4Discovery board works fine with its
on board programmer.

I would think that perhaps:
* I might be connecting to the wrong pins on the programmer? Although
I see the signals I expect, cleanly, on the scope.
* I might have signal integrity issues? I did see (0.5V amplitude on a
3v signal) ringing, but a low value resistor in series took care of
it.
* I might be connecting to the wrong pins on the microcontroller? I
know this isn't the case for the development board
* My jumpers are in some way faulty? Although, they are shorter than
the ribbon cable supplied with the programmer and I can see the
signals fine on my scope.
* My chips might be bad? Although, I tried three separate chips,
including a known good one


Does anyone have any ideas as to what might be wrong?


Thanks,
Jason White

Other miscellaneous notes:
* It seems when the device boots, the reset pin NRST (which is also an
IO) goes low. I'm not sure if that is normal.
* The open source utility reports the chip id as bouncing in between
0xe0042000 when disconnected and 0x20002e60 (0x2000 -> revision 2,
then the rest is garbage) when all of the connections are right. It
reports the same value for multiple types of chips and for both
programmers.

[1] AN4080: Getting started with STM32F0xx hardware development
http://www.st.com/web/en/resource/technical/document/application_note/DM000=
51986.pdf
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