MVSFORUMS.com

[blueash]

Can we use UNIT=3490 for reading square tapes?

Can someone please provide the link to any manual which tells how to code UNIT for different tape types. Is it shop specific or generic.

Thanks for all your help.

[bablack]

The doc on UNIT= is in the IBM JCL Reference manual.

The values can be:
1 specific unit addresses, e.g., UNIT=03A5, hardly ever used for tape/disk
2 generic device types, e.g., UNIT=3390, UNIT=3490. These are provided by IBM depending on what device types exist in your configuration. The JCL Ref manual says "get a list of device types you can specify from your installation".
3 generic name (or "group name"). this is defined by your installation and can be any name up to 8 chars, e.g., UNIT=CART might be used in your installation for cartridge (square) tapes.
Check with whoever maintains your I/O config for valid device types and generic names.

UNIT=3490 will allocate an IBM 3490E drive (or a compatible drive from another vendor). 3490E drives can read tapes in 3480 or 3490E format but can write only in 3490E format (3480 and 3490E use the same cartridge). If you have 3490E or compatible drives, this will work. If not, you will need a different value.
_________________
Bruce A. Black
Senior Software Developer
Innovation Data Processing

[blueash]

Thanks Bruce.

Link to IBM JCL reference for UNIT as Bruce mentioned