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The front panel must be holding the processor in the
stopped condition for the SINGLE STEP switch, the
DEPOSIT/DEPOSIT NEXT switch, or the EXAMINE/EXAMINE
NEXT switch to operate.
The EXAMINE/EXAMINE NEXT switch provides the facility
for observing what is stored in memory in any location
or for setting the program counter to any desired
location to initialize program execution there.
When examining the contents of a location in memory,
the 16 address switches are used to enter the 16 bit
address.
This 16 bit address is normally said to be
divided into two 8-bit sections labeled high order and
low order. . The high order address is on the left hand
side of the panel, and the low order address is in the
center.
The low order byte contains bits 0 through 7
and the high order byte contains bits 8 through 15.
When only a small amount of memory is being used the
high order bits are normally 0 and the switches must be
in down position, unless the address jumper selection
on the memory board is wired otherwise.
When the EXAMINE switch is actuated, the processor jumps
to the address location set in the 16 address switches
and is stopped during the fetch cycle out of that
memory location.
dicators will show the address set in the 16 address
switches and the data bus indicators will show the
contents of that memory location.
locations in memory may be observed by setting the 16
address switches to that desired address and actuating
the EXAMINE switch again.
is actuated, the address shown in the address bus in
dicators is incremented by 1 and the contents of that
following memory location are displayed on the data bus
lights.
Thus, a program or data would normally be check
ed by setting the first address in the address switches
and actuating the EXAMINE switch to see the fist byte,
and thereafter actuating the EXAMINE NEXT position to
observe each succeeding byte of data or program.
At that time, the address bus in
When the EXAMINE NEXT switch
CP-A
User Guide
Revision 1
Any additional
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