RTOS/AM5716: I got strange issue of UART , it not received 0xFF while looping test between UART1 and UART2 of AM571X.

Jae Yong Koh

Intellectual 430 points

Part Number: AM5716
Other Parts Discussed in Thread: SYSBIOS

Tool/software: TI-RTOS

Hi,

I'm testing UARTs of AM571x custom board and I got the strange issue

Looping UART1 & UART2 and sent data from one UART and receive other UART.

It works but I got the strange problem when sending 0xff.

0 ~ 0xfe : it's OK

0xff : could not receiving it.

I sent data ( 0 ~ 0xff and 0 ~ 2b (300 byes) from UART2 -> Looped UART1 but not received only 0xff.

not received 0xff on other tests.

I'm using pdk_am57xx_1_0_10 with SYSBIOS as below

UART1, UART2 parameter are as below and I used UART_OPEN/UART_write/UART_read API

/* UART parameters structure polled mode*/
const UART_Params user_params = {
UART_MODE_BLOCKING, /* readMode */
UART_MODE_BLOCKING, /* writeMode */
SemaphoreP_WAIT_FOREVER,/* readTimeout */
SemaphoreP_WAIT_FOREVER,/* writeTimeout */
NULL, /* readCallback */
NULL, /* writeCallback */
// UART_RETURN_NEWLINE, /* readReturnMode */
// UART_DATA_TEXT, /* readDataMode */
// UART_DATA_TEXT, /* writeDataMode */
UART_RETURN_FULL, /* readReturnMode */
UART_DATA_BINARY, /* readDataMode */
UART_DATA_BINARY, /* writeDataMode */
UART_ECHO_OFF, /* readEcho */
115200, /* baudRate */
UART_LEN_8, /* dataLength */
UART_STOP_ONE, /* stopBits */
UART_PAR_NONE /* parityType */
};