STM CircleOS forum / 3 UARTs

multiaxis · 2010-10-13 00:09:03

Hello,

I plan to use a primr2 for a project that i have yet on pc.
I need two uarts plus one i2c or uart.
(The third connection will transfer data only one way into the stm)

I read page 8/9 in the manual and read some posts here in the forum, but i am still a bit confused about the possibilities.
Is the i2c input blocked, when I use two uarts on the extension board?

is there maybe another solution ?

best regards

yrt · 2010-10-13 06:50:04

Hi,

Effectively, UART2 and UART3 are available on extension board, if UART3 is remapped on PB6/PB7 pins of the STM32, but these pins are shared with I2C1.
So using UART3 and I2C1 are exclusive on extension board.

A solution may be to modify the Primer2 board by removing the IrDA chip, in order to get the UART1 pins (PA9/PA10 µC pins).

Yves

multiaxis · 2010-10-13 08:02:51

Thanks for your response,

I think a part of my confusion relied on a mistake in the manual.
PB 6/7 are linked with UART1 rx/tx instead of UART3 rx/tx.

I mean, if it is no mistake, if remapping rx/tx on PB6/7 means stealing UART1 rx/tx from the IrDA, then the plan with the IrDA won't work, or not?

yrt · 2010-10-18 06:41:51

Sorry for my mistake ! I don't know what I swapped USART1 & 3 : it is well USART1 on PB6/PB7 when remapped ! The Primer2's manual is correct.
But I confirm that you can use I2C1 on PB6/PB7, and remove the IrDA chip to get USART1 on PA9/PA10 (not remapped).

# 1 2010-10-13 00:09:03 3 UARTs

3 UARTs

# 2 2010-10-13 06:50:04 3 UARTs

Re: 3 UARTs

# 3 2010-10-13 08:02:51 3 UARTs

Re: 3 UARTs

# 4 2010-10-18 06:41:51 3 UARTs

Re: 3 UARTs

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