Hi,

I am transmitting data with a program by the ttyS3 with linux kernel 2.6.16, but when I use the Linux kernel 2.6.21, this program does not transmit data. The program is the same in both kernel, I modified in /arch/arm/mach-at91/board-dk.c this .nr_tty = 5, .tty_map = { 4, 1, 2, 3, 0 } /* ttyS0, ..., ttyS4 */ in both kernels but in the kernel 2.6.21 the pin of the Arm dosen't move.

Thanks in advance
Jeronimo

Are you using the hw handshaking (RTSCTS, configurable with "stty -F /dev/ttyS3 -crtscts")? Check out the pin multiplexing configuration in arch/arm/mach-at91/at91sam9261_devices.c. On some ports, the RTS/CTS pins are not muxed by default and as they are pulled up, it may block traffic.

Hi,

I am not using hardware handshake.
I modified in arch/arm/mach-at91/at91rm9200_device.c this function, enabling the RTS and CTS pins, but the serial port doesn't transmit

static inline void configure_usart3_pins(void)
{
at91_set_B_periph(AT91_PIN_PA5, 1); /* TXD3 */
at91_set_B_periph(AT91_PIN_PA6, 0); /* RXD3 */
at91_set_B_periph(AT91_PIN_PB0, 0); /* RTS3 */
at91_set_B_periph(AT91_PIN_PB1, 0); /* CTS3 */
}

Thanks
Jerome