Software 4.5 Programming modules The user program of Eco Control 667E is structured by modules. This helps you to break up the technological pro- blem to be controlled into separate part tasks. The modules form a hierarchical system (at max. 5 levels) that allows modules at higher levels to call modules at lower ones. A program of this structure is very clear and helps a lot with understanding or updating of finished programs. The fol- lowing types of modules are available: Ш organisation module Ш program modules Ш KUBES modules Processing of individual modules is monitored by a watchdog which is triggered every time a module is called. After that the system has 70 ms to process the module.
Program and KUBES modules are subroutines. The return to the calling module is ensured by the module organisation and must not be programmed separately. Modules must not call themselves. The maximum length of a module is 128 instructions. To these you may add extra comment lines so that the maxi- mum number of lines is 253. 65