[Gumstix-users] ttyS3 and audiostix

[Darren G. <ts...@ya...>]

With the gumstix basix and the latest uboot, and r406, I should be able 
to use HWUART on the Audiostix, right?  I'm not using bluetooth.

If I try without any extra configuration, I see TX bytes on HWUART

> cat /proc/tty/driver/PXA\ serial
> 0: uart:FFUART mmio:0x40100000 irq:15 tx:38153 rx:408 
> RTS|CTS|DTR|DSR|CD|RI
> 1: uart:BTUART mmio:0x40200000 irq:14 tx:0 rx:0
> 2: uart:STUART mmio:0x40700000 irq:13 tx:0 rx:0
> 3: uart:HWUART mmio:0x41600000 irq:0 tx:99 rx:0

but no signal on the pad.

If I do this as suggested by the Waysmall FAQ:

modprobe proc_gpio
echo AF1 out > /proc/gpio/GPIO48
echo AF1 in > /proc/gpio/GPIO49
echo AF1 in > /proc/gpio/GPIO50
echo AF1 out > /proc/gpio/GPIO51
for i in 42 43 44 45;do echo GPIO in > /proc/gpio/GPIO$i;done

I get errno 11 when I try to write to ttyS3.

Is there a step I'm missing?


thanks,

darren