How does CA ASM2 utilize $OPTIONS $TPUNIT values during reload processing? How does it work?
CA ASM2 stores the device type information of the unload tape device in the IPC (Integrated Product Catalog). This is not the esoteric name but the actual device type.
If you have an IDRC device defined with the esoteric of 3490 then you would be using the UNIT=CART definition in the CA ASM2 archive JCL. In the IPC the device type information is stored, "not the esoteric". Esoterics can change but the device types always remain static.
Device type for a 3490 is 78008082. So, in the IPC, the value 78008082 is stored for reload purposes in the future.
In the $OPTIONS $TPUNIT filed we have the following:
$TPUNIT EQU * USER MODABLE
$TP3420 DC CL8'RTAP ' UNIT NAME FOR 3420 ALLOCATIONS
$TP3480 DC CL8'CART ' UNIT NAME FOR 3480 ALLOCATIONS
$TPM860 DC CL8'M860 ' UNIT NAME FOR M860 ALLOCATIONS
$TP348X DC CL8'3480 ' UNIT NAME FOR 3480 XF DRIVES @IDR
$TP349E DC CL8'3490 ' UNIT NAME FOR 3490 E ALLOCATIONS
$TP359E DC CL8'3590-1 ' UNIT NAME FOR VTAP ALLOCATIONS
DC CL8' ' UNIT NAME TABLE EXPANSION
When a reload from IXR, $RA, or $RB is processed, ASM2 will take the "first device type match" that was stored in the IPC. In our example ASM2 has the label $TP349E defined as esoteric 3490. So the reload process would request an esoteric of UNIT=3490.
The labels in $TPUNIT are defined internally and you cannot change the label names or add lines to the $TPUNIT fields.