I currently have an embedded device attached to the PC via a serial port. I'm having trouble getting data on PC when I use my PCI serial port card, I'm able to get the data immediately (no delay). When I use the motherboard built in my USB-to-serial plug or serial port, I should have read data (40ms for 32 MB packet) delay.
The difference between the hardware I can find is that the UART uses PCI card 16650 and uses the plug / motherboard standard 16550A. PCI card is set to disrupt 28 bytes and the plug is set to inhibit 14 bytes.
I'm connected to 56700 baud (if it helps).
The delay is the majority of the duty cycle and in fact the transfer time increases (10 minutes transfer versus 1 hour transfer).
Does anyone have an explanation for why I use delay with plug / motherboard? Can anyone recommend possible solutions to reduce or remove this delay?
There is an ASVNC_LOUNCACI flag for the serial in Linux Driver which can help you use any driver , He may be something similar.
However, there should be no difference on the bulk transfer of latency. It should add 40 ms at the beginning of the transfer and this is the reason that the drivers do not worry about it in the first place, if you are doing 32-byte packets on that baud rate and latency, then I have about 100 With the window size of the packet, I recommend using your transfer protocol. In other words, if you have not received ACK for packets sent before 100 packets, then you want to stop transmitting.
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