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Michael Mrozek
Michael Mrozek
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You state that you have only 2 physical serial port which you detect to ttyS1 and ttyS2.

  ttyS3 and ttyS4 don't exist,exist; they are exposed, but you have to ignore them.

  This is simply the way the driver works,works; it probes what may be a serial port and expose it to you, but you have to verify it is a real serial port because the driver can't be 100% sure. This line:

ttyS3: LSR safety check engaged!

tells you that the serial port ttyS3 is not ready, and in your case it'll never be because it doesn't exist. The driver does its best to correctly detect the serial ports, but sometimes it fails. When that's the case you have to find which interfaces exposed are really connected to the hardware manually which you've already done.

You state that you have only 2 physical serial port which you detect to ttyS1 and ttyS2.

  ttyS3 and ttyS4 don't exist, they are exposed but you have to ignore them.

  This is simply the way the driver works, it probes what may be a serial port and expose it to you, but you have to verify it is a real serial port because the driver can't be 100% sure.

You state that you have only 2 physical serial port which you detect to ttyS1 and ttyS2. ttyS3 and ttyS4 don't exist; they are exposed, but you have to ignore them. This is simply the way the driver works; it probes what may be a serial port and expose it to you, but you have to verify it is a real serial port because the driver can't be 100% sure. This line:

ttyS3: LSR safety check engaged!

tells you that the serial port ttyS3 is not ready, and in your case it'll never be because it doesn't exist. The driver does its best to correctly detect the serial ports, but sometimes it fails. When that's the case you have to find which interfaces exposed are really connected to the hardware manually which you've already done.

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rafirafi
rafirafi
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You state that you have only 2 physical serial port which you detect to ttyS1 and ttyS2.

ttyS3 and ttyS4 don't exist, they are exposed but you have to ignore them.

This is simply the way the driver works, it probes what may be a serial port and expose it to you, but you have to verify it is a real serial port because the driver can't be 100% sure.