[En-Nut-Discussion] AT91SAM7 UART h/w flow control or DMA

[Ben Hoyt]

Hi guys,

I'm interfacing the AT91SAM7 port of NutOS with a modem that requires
RTS/CTS flow control. But as far as I can tell the USART driver (low level
parts in arch/arm/dev/usartat91.c) doesn't support this. Well ... there's
support for it, but it looks AVR-only and is essentially commented out. It
looks like it wouldn't be too much work to port it over, but there are a few
hardware-dependent bits.

Plus, it's done in software, and the AT91 supports a nice RTS/CTS hardware
flow control mode ("hardware handshaking"). But it only works in DMA (PDC)
mode (for reception, at least).

Anyone else using AT91 NutOS UARTs with flow control with, or DMA for that
matter?

Cheers,
Ben.

-- 
Ben Hoyt
Mobile: +64 21 331 841
http://www.benhoyt.com/