AMX 68000 Target Guide
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ISP Type
Your fast clock ISP is identified as such by selecting Fast Clock Handler from the pull
down list.
ISP Root
Edit the default name ---New--- to provide the name you wish to give to your fast clock
ISP root. The ISP root name is used to identify your fast clock ISP in the ISP list.
The ISP root is a function created by the AMX Configuration Builder in your Target
Configuration Module. The function entry point is declared with a public symbol defined
with the name you provide. The name must be unique and must conform to the symbol
naming conventions of your assembler.
Clock Service
Your clock device will be serviced as follows:
Write Value #1 to the device port at memory Address #1.
Delay for the number of µs defined as I/O Delay (µs).
Write Value #2 to the device port at memory Address #2.
Address and Value
Each address parameter specifies the 32-bit, hexadecimal value of an absolute memory
address which, when referenced as an n-bit value, is decoded by your target hardware as
a reference to your clock device. Each value parameter is an n-bit, hexadecimal value
which must be written to the device port specified by the associated address in order to
dismiss the clock interrupt.
If your clock device only requires that one value be written to one device port, leave
fields Address #2 and Value #2 blank (empty).
I/O Delay (µs)
Your target hardware may not operate correctly if two sequential device I/O references
are issued at the processor's instruction execution speeds. If this is the case, you can
force the fast clock ISP to inject a delay of n µs between the I/O device ref erences by
entering a non-zero value into this field.
If your clock device requires no delay or only requires that one value be written to one
device port, leave the I/O Delay field blank (empty).
Write Size
From the pull down list, select the number of bits (8, 16 or 32) which must be written to
the clock device. The least significant n bits of each value will be written to the device.