The RLE support in the aux driver code uses SOB, which is an EIS instruction and unavailable on older PDP-11s, such as the PDP-11/22, /05 and /04, or un-expanded /40s and /03s. This can make it seem like there is a hardware fault with the connected machine, when there isn't.
Workaround: uncheck the "Test RLE compression" button and press "Test" once. This will disable RLE compression for the entire session.
Aside from fixing the driver, it might be useful to move the checkbox out of the "Test" section and make this a global RLE enable/disable for the serial port, set at the time of performing any operation.
This appears to have been realised at least once before, but not completely resolved.
The RLE support in the aux driver code uses SOB, which is an EIS instruction and unavailable on older PDP-11s, such as the PDP-11/22, /05 and /04, or un-expanded /40s and /03s. This can make it seem like there is a hardware fault with the connected machine, when there isn't.
Workaround: uncheck the "Test RLE compression" button and press "Test" once. This will disable RLE compression for the entire session.
Aside from fixing the driver, it might be useful to move the checkbox out of the "Test" section and make this a global RLE enable/disable for the serial port, set at the time of performing any operation.
This appears to have been realised at least once before, but not completely resolved.