AnsweredAssumed Answered

Pin mapping USB and JTAG/TRACE

Question asked by claxton.dean on Jun 17, 2011
Latest reply on Jun 20, 2011 by alokm
Hi everyone,

I've just ordered the STM3220G-EVAL, but while waiting for it to arrive, I'm looking at pin mapping for my application.

In particular I have a couple of questions in regard to USB FS, and JTAG/TRACE.

USB FS
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If I use port PB14 (OTG_HS_DM) and port PB15 (OTG_HS_DP), must I use port PB13 for Vbus as per the datasheet? Looking at the alternate function mapping I cannot see any particular mention of having to use PB13 for a specific function. Can I use any GPIO port?


JTAG/TRACE
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Is there a bare minimum recommendation of port pins to reserve for JTAG/TRACE? 

For example, does the serial wire have the same capabilities as the full JTAG? If I can get away with serial wire pins only, then I can free up SPI1.

Also in regard to trace there seems to be many different configurations - is there a bare minimum recommended, or can I get away without trace at all?

I'm completely new to STM32 (and to ARM Cortex full stop) - the remapping exercise is pretty interesting. Looks like NXP do the same with their LPC1850, but I cant get Ethernet AND SDIO out on theirs!

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