VISA delay

[SUIP]

Hi, 

I'm sending data to a st mc and the mc sends back the exact same message and are comunicating using visa read/write and uart. The data stream is continuous and im using a special character to measure the round trip time. Im expecting some delay but the total delay between sending and and receiving is usually more than 4sec. Is there a way to reduce this time? The mc is just receiving and sending back. 

labview -> mc seems to be instantaneous (VISA Write -> Uart_receive), the slow is prob in the mc -> labview (Uart_transmit -> VISA read). 

The baudrate, com port are the same, visa write expects one byte, everything in a 1ms while loop, no termination character 

[daveTW]

Hello SUIP,

what does "st" and "mc" mean?

4 seconds delay seems very long. Have you tried "Serial Write and Read on Two Ports.vi" from the Find Examples- dialog in the Help- menu?

[SUIP]

Sorry I didn't specify, I'm using a stmicroelectronics microcontroller, I'll check using the vi you mentioned

[crossrulz]

Share your code. We have nothing to go by until you do. But my gut feeling is that you are not properly using a termination character as the 4 seconds sounds like a timeout.

[RTSLVU]

Most serial communication issues can be solved by watching this video: VIWeek 2020/Proper way to communicate over serial