2012-11-08 10:00 AM
My hardware guy tells me that most of the SOC peripherals don't make it out to the header pins on this board. He says they are tied up with board supported peripherals.
1) In general is this true? Is this board designed to allow external hobbyist bread boarding, where one plays with the internal periphs like counter/timers, gpio, etc? 2) Where are the ''actually available'' connections documented. 3) Here is the list of what we need... I have done a serial uart loopback test already so I though that part was good but he says one the boards push-button is connected and just not interferring....1. 32 bit timer frequency input
2. One capture pin for the 32 bit timer chosen.
3. A divider (by 32000) that can use the input from the 32 bit timer
4. An output pin for that divider
5. A UART I/O 2 pins
6. An I2C I/O 2 pins
7. Two GP input pins. He told me: I can't find it. (them) Thanks in advance! #header-pins2012-11-08 11:29 AM
All the board documentation is here:
http://www.st.com/internet/evalboard/product/252419.jsp
The User Manual contains schematics and pinout tables:http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/USER_MANUAL/DM00039084.pdf
2012-11-08 02:40 PM
It has a reasonable mix of internal and external peripherals.
Using a couple of USART, with SDIO and TIMs here. You'd have to do your own due diligence via the schematic and user manuals to see what you can or can't get out. People have posted Excel sheets before, and there was a MicroExplorer tool. These boards will always be a compromise, a feature fit for one individual is a bane for others. Generally you're not going to be able to escape all peripherals simultaneously, or do DMA to all channels/devices, and you might have to do some juggling to get the mix or subset you want. The F4 parts have a more flexible muxing scheme than the older F1 parts. If you want more of a breakout board there have been several on eBay, including unpopulated PCB for a couple of dollars. The chips also come in high pin-count packages to help escape peripherals.2012-11-08 05:06 PM
Thanks. The UM has the scary details. We will have to test out that all the muxed signals don't interact/interfere with our use.