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board STM32-E407

Started by bexizuo, July 01, 2013, 12:35:41 pm

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July 01, 2013, 12:35:41 pm Last Edit: July 01, 2013, 01:27:30 pm by bexizuo
Dear Olimex,

i'm very unsatisfied with the board STM32-E407,
i want to flash it and debug it using serial port together with the device on UEXT's SPI,
but the processor supports only USART1(PA9/PA10) or USART3(PB10/11 and PC10/11) to use for flashing,
let's see:
PA9 PA10 ... USB_OTG1
PC10 ... SD_D2

i don't need USB_OTG1 or SD slot, but there is no switch or jumper to disconnect it,
so i'm unable to flash&debug using USARTs,
it's very hard for me to use it, i also wrote 2 other posts considering this board and i still don't have answer, it seems that this board is useless for me :-(

i'm not sure if you read the reference manual for processor, there is this sentence:
"Due to the fact that the switch only sinks a limited amount of current (3 mA), the use of
GPIOs PI8 and PC13 to PC15 are restricted" ...
and you put LED on PC13 :-(

and i also was hoping that this board will be ready for USB2.0 HighSpeed but this is also disappointment,
there is missing ULPI for HighSpeed,
there is also mistake in user manual, there is LAN connector pinout different than the board is having,


Too bad it didn't work out.
Sections 1.1 (Features) and 2.2 of the manual pretty clearly describe the use of JTAG port for debugging / programming.
Using a 2mA LED on a port capable of sinking 3mA isn't bad.
The missing high speed USB would have been nice, I agree.

Not sure about the Ethernet pinout error - which pin was wrong?


well, i don't have budget to buy jtag device, i will not buy it, i want to flash/debug it only on USART,
i don't know current of LED, i know that standard LEDs using approx.20mA,
and considering LAN pinout, if you study user manual for the board:
section 6.6:
1- TX+
2- TX-
3- Vdd
7- RX+
8- RX-

but standard for RJ-45 is:
1- TX+
2- TX-
3- RX+
6- RX-
and no Vdd ,
1 pin is differently connected and second is not connected,


It would appear the pinout described for the LAN connector in section 6.6 of the manual is showing the pinout for the internal side of the connector and not the external side. Definitely an error in the manual, but if you look at the schematic, the connector is correctly wired on its external interface.

If you want USART function and don't need OTG1, then take a soldering iron and remove R43 and attach a wire to the pad that connects to PA9. For the RX line, just solder a wire to the pin of D2 that connects to PA10. D2 is not placed on the board, so it is easy to solder a wire to the pad.


Hi billr,

you are experimentator :-)

i don't know if there is any connector in user manual that is having different pinout on external and internal side, i'm not sure if manual has idea to document "internal"/PCB pinout for LAN connector, it looks like it's from earlier versions and last version is RJ-45 correct,

and considering OTG1 means that i will loose DFU possibility, second/last possibility to program processor if i don't use USART, of course in case if i don't have JTAG/SWD device,
from my experiences i don't have tested OTG2 for DFU,
and SDIO i will need in application for grabbing some data,

so finally design could be better for programming without JTAG/SWD and user manual should be updated


So don't remove R43. Just attach the wire to the side that connects to PA9 and it should still work. You will be able to use the OTG1 fro DFU if serial interface fails.


well, fortunately i made board with FTDI4232 earlier, so i have 4 serial ports and i'm able to use the board, but generally i'm disappointed from the design of the board, i have to use 2 USARTs for my application,