4. CONTROL OF VIX DRIVES 59

Fault Status Reporting
Faults are classified into two groups:
Drive Faults DF (hardware faults present in the drive)
or User Faults UF (user program faults)
Drive Faults
Hardware drive faults cause the drive output stage to turn OFF (de-energised). This will
cause the Drive LED to turn RED. Once the fault has been corrected the drive may be re-
energised using the ON command.
When read, DF reports a 32-bit double word pattern of the form:
*0000_0000_0000_---32 bit wide double word---_00001458 32Bit No.
Where a bit is set (displayed as a 1) its bit number can be determined and compared with
the bit number value given in Table 4-5 to determine the Drive Fault being reported.
Use the Read command to display the DF word pattern, that is ‘aR(DF)’.