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AMX 68000 Target Guide
4.4 Defining a Fast Clock ISP
At least one of your ISPs must service a clock interrupt which provides AMX with its
fundamental clock tick at the frequency and resolution defined in your AMX System
Configuration Module. For many applications, your clock ISP will just be a standard
AMX conforming ISP defined in the ISP Definition window. It is distinguished from all
other ISPs by picking Clock Handler as its ISP Type.
Rarely does the Interrupt Handler for your AMX clock ISP have to do anything except
dismiss the clock interrupt request. This is frequently accomplished by simply writing a
command to a device I/O port. For such clocks, the AMX Configuration Builder lets you
create a fast clock ISP without having to write any code at all.
To create a fast clock ISP, go to the ISP Definition window, click on the Add button and
select Fast Cloc k Handler as the ISP Type. Then fill in the description of the operating
characteristics of your clock device. The layout of the window is shown below.