0P19 UNDETR ERR Cause: Unit check (no valid sense byte). This is probably a hardware error. l Programmer Action: In addition to the hardware errors that can cause this message, a data check or UCS parity error in a UCS 1403 will cause this message if the PUB for this device does not specify UCS. Use a dump to determine the failing device type as follows: 1. Display and record the address of the communications region, bytes X'16" and X'17' of low real storage, before the dump is executed. 2. Add X'40" to the address obtained in step 1. This location contains the address of the PUB table. 3. Search the table until the PUB device address matches the device address in the error message. Each PUB entry is eight bytes long, and the first two bytes contain the channel and unit (X'0cuu') of a device (see Figure 5).
4. When a match is found, obtain the device type from byte 4 of the entry and determine the device type using Figure 6.
Operator Action: See Figure 4 at the beginning of this section. If the job is canceled, mount the file on another device and rerun the iob. lf the problem recurs, have the · system dump · ROD command output · EREP output (see DOS /VS SADP) · log sheet available for problem determination.
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