3180 in partitioned format mode

IMS support for the 3180 in partitioned format mode is provided through 3290 partitioning and scrolling support.

Although interaction with the 3180 and the 3290 in partitioned format mode are similar, the following differences apply:

• With the 3180, only one partition with specific size limits is possible. The 3290 supports multiple partitions of various sizes.
• Logical unit display screen size and viewport location for the 3180 cannot be specified in picture elements (pels). The 3290 supports rows, columns, and pels.
• With the 3180, the single partition is the only one initialized. With the 3290, the application program can determine, with the ACTVPID keyword, which of the various partitions to initialize.

Because only one active partition is available on the 3180, you can either specify Option 1 on the PAGINGOP= operand of the PDB statement or accept the default of 1. With this option, the initial data stream presented to the 3180 LU consists of the first logical page of the output message, which is mapped by the DPAGE to the single partition. When you request the next logical page, MFS gets the logical page that is sequentially next in the message and sends it to the partition.

Clearing the display and scrolling is handled in the same way on the 3180 as on the 3290 in partitioned format mode.