Service manual

Chapter 5 E40S/E60S Fault Finding
FileStore Service Manual 100
See Fig 9 for a diagram of the typical waveform produced:
Figure 9: E40S/ E60S start-up waveform
The above figures are approximate and will enable checks to be made for open/short Circuits
and malfunctioning components.
5.2 Address decoding
To test the address decoding, execute a program to access the relevant memory location. This
is done by the SCSI interface tests in the FServTest program of the FileStore test software.
See Appendix A - Test Equipment at the back of this manual for further details.
5.3 Hand shaking
To test the SEL/BSY handshake, use the handshake test of the SCSI interface tests in the
FServTest program of the FileStore test software. See Appendix A - Test Equipment, for
further details.
5.4 Bus lines
When the buses are not being asserted by the host system, ie in the bus free phase, all bus
lines will float according to the values of their terminating resistors.
Measure the voltage of each bus line in turn and make sure that none of them is stuck at +5V,
which would indicate a short circuit, or at 0V, which would indicate that there was a short
circuit.