I have problem about interbyte time with application using uart driver on raspberry pi 2. Interbyte time is time that each data byte sent via UART is delayed from the previous byte. With my application has interbyte time > 3ms, this time is too long.

  • This is some parameter in my application : byte 1 is 0xAA, byte 2 is 0x00 , 1 start bit, 1 stop bit, baud rate is 9600. Bellow is wave form with time between 2 byte data too long.

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  • In another case, I write a simple use directly uart driver to send 1 byte in a loop with some parameter : data byte is 0x00, baud rate is 9600, 1 stop bit. Interbyte time is this case is about 150us, it can accept.

enter image description here

Can you suggest me a solution to reduce time delay in case 1, interbyte time is too long (>3ms )

I'm looking to respond from you ! Many thanks !

  • We need to see the code you are using on the Pi to write the data. – joan Mar 25 '16 at 9:27
  • Sorry, I can't public because source code have to keep for NDA company. The same issue from my team on imx6 already fix by update latest source code for uart driver, but in this case I don't know what root cause and what we need to change from source. community.freescale.com/thread/383199 – dongpham Mar 25 '16 at 12:00
  • Given that the error is in your code this presents a problem. You had better write some code you can publish but which exhibits the same behaviour. – joan Mar 25 '16 at 12:06
  • Since the start bit is a one, it looks like 0x55 and 0x7f, to me. – PaulF8080 Mar 28 '16 at 1:22

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