AT91 USART configuration

Hi, I am having problems setting up the USART on an AT91FR40162.

The AT91FR40162 is an AT91R4008 integrated with a 2MByte flash chip.

Basically, I disable P14 (TXD0) & P15 (RXD0) from the peripheral controller so that they may be used by the USART.

I then:

  1. Disable and reset the receiver and transmitter in US_CR (control register).
  2. I then set 8,n,1 MCLK in US_MR (mode register).
  3. Write the divider into US_BRGR (baud rate register).
  4. Enable receiver and transmitter in US_CR.
  5. At this point, the TXREADY and TXEMPTY bits are turned on as they should be in the USART status register.

My problem, no matter what value I write to US_BRGR, in step 3 above, it alway remains 0, what could be causing this, I have obviously missed something but what? Needless to say the USART does not work, even if I set it to local loopback.

Help, any advice would be greatly appreciated, Regards, Clive

Reply to
Clive Levinson
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I have no problems with AT91M40400, AT91M40800 and AT91R40008.

Please post the crystal frequency and the exact bit patterns and addresses they are written to (both parallel port and USART).

Tauno Voipio tauno voipio @ iki fi

Reply to
Tauno Voipio

Likewise, it bit me too.

Reply to
FLY135

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