80C535 hardware/assembler course (3):

Since the CCU (compare/capture until of the 80C535 is functionally related to interrupts in general, these two subjects are discussed along side each other in the present course instalment. When used in capture mode, the CCU enables, for instance, accurate time measurements to be performed by software. Similarly, the compare mode may be used to program a generator for variable pulse width signals. The timing of the CCU is arranged by Timer 2 in the 80C535. Same of the features of Timer 2 will be discussed here. Only a handful of components, and simple programs, are required to become familiar with the ins and outs of the CCU. As usual, the relevant programs may be found on your course disk.