The original pin function related to the UART0 port shows below:
- 001.jpg (130.8 KiB) Viewed 27111 times
FUNC : PIN NAME
U0TXD --> U0TXD
U0RXD --> U0RXD
U0CTS --> MTCK
U0RTS --> MTDO
These pins can operate in a full duplex way with hardware handshake(flwo control).
config details --> viewtopic.php?f=7&t=48
On esp demo board, this picture shows a basic debug environment:
- 002.png (663.8 KiB) Viewed 27111 times
2. uart debug info. output:
Usually,for iot project , UART0 can output the debug information. But in AT mode , UART0 communicates with the PC or MCU, so the debug info. should be output via UART1.
(1).SET UART1 PIN FUNC:
PIN_FUNC_SELECT(PERIPHS_IO_MUX_GPIO2_U, FUNC_U1TXD_BK);
(2).change output port for os_printf:
os_install_putc1((void *)uart1_write_char);
3. how to prevent uart0 output when the chip is booting up.
see --> viewtopic.php?f=7&t=22