Epson C82315 - Manual (Page 31)

INPUT NOT INDICATING BUSY
This is an ASIC internal test during a transmission, and indicates an ASIC
failure.
TWO BYTE DATA CHECKS BAD
This test verifies multi-byte data transmissions for proper data. A failure
could be caused by a -5-volt supply problem, a transmitter circuit failure,
a receiver circuit failure, or an ASIC failure.
OVERFLOW COUNTER BAD
This tests the protection circuit-in the ASIC designed to prevent a host
failure from over-filling the interface buffer and causing an error in opera-
tion. This message indicates an ASIC failure.
BAD DATA, EXPECTING XX RECEIVED XX
A byte of data was sent, and the receiver circuitry interrupted the
microprocessor. However, when the data was checked, it was not the
same as when it was sent. This would indicate a problem with the
twin-axial circuitry data paths.
PARITY ERROR DETECTED or PARITY FAILURE
This error indicates that the twin-axial receiver detected a parity error on
receiving polls or data. This would indicate an error in the parity genera-
tion by the twin-axial output, malfunctioning of the parity checking circuit
of the twin-axial receiver, or a poor cable connection.
INTERFACE DIAGNOSTIC LOOPBACK
Interface diagnostic loopback is essentially the same as interface diagnostics; the
only difference is that no error messages are generated. A qualified technician can
use this test to check the circuitry with an oscilloscope.
Interface diagnostic loopback is performed in basically the same way as interface
diagnostics; however, you must turn switch 8 off before starting. Always return
switch 8 to the on position when you are finished with interface diagnostic
loopback.
24