Entity and instance IDs

Each application must have a unique entity and instance ID for routing messages among the processes in the system. Entity IDs are single byte values in the range of 0x00 through 0xFF, assigned by the application developer. Entity IDs are allocated as follows:

Range

Usage

0x00 - 0x1F

0x80 - 0xFF

Reserved for use by system utilities, configuration utilities, and management utilities.

0x20 - 0x7F

Available for use by applications.


Instance IDs identify the processor on which the entity executes. The host is always processor 0 (zero). Therefore, all host-resident TUP applications must be coded to 0 (zero). All tasks on TX board number 1 receive an instance ID of 1. All tasks on TX board number 2 receive an instance ID of 2, and so on.