Reading latency #4
Description
Hello, I am using the PCIE-1602 board with the Linux driver adv17v35x v. 2.6.37. I had to make some minor changes in order for it to be compiled against my kernel (with the RT_PREEMPT patch) version 6.1.46-rt14-rc1. Attached the modified source code.
It works fine, but I am trying to minimize the latency in reading 8-byte messages received via RS485 (1Mb/s, 8, N, 1) from a microcontroller board.
I am using a blocking read() configured with VMIN = 0 and VTIME = 1 inside a real-time thread, and the call takes between 300 and 500 µs, after which it always returns all 8 bytes.
I tried reducing RXTRG from the default value (32) to 8, but without noticing any significant changes.
I am wondering how I can reduce this latency (and the resulting jitter) in order to be able to read these messages at a higher frequency.
I hope that you can help me.
Thank you very much