Programming instructions

EXAMINE
EXAMINE NEXT
DEPOSIT
Console Key
START
Function
Starts the processor. The first instruction is
taken from memory cell specified by the
setting of the ADDRESS. switches. The
START operation clears the AC and Link,
and turns off the Program Interrupt.
STOP Stops the processor at the completion of the
memory cycle in progress at the time of key
operation.
CONTINUE Causes the computer to resume operation
from the point at which it was stopped by
the last previous operation of STOP or one
of the EXAMINE or DEPOSIT keys. Besides
the normal off and momentary on positions,
CONTINUE has a latched on position ob-
tained by ralsing the key instead of de-
pressing it.
Places the contents of the memory cell
specified by the ADDRESS switches in the
AC and MB. The contents of the ADDRESS
switches appear in the MA. The PC contains
the address of the next cell.
Places the contents of the cell specified by
the PC in the MB and AC. The C(PC) are
incremented by one. The MA contains the
address of the register examined.
Deposits the contents of the AC switches in
the memory cell specified by the ADDRESS
switches. The C(AC switches) remain in the
AC and MB. The contents of the ADDRESS
switches appear in the MA. The PC contains
the address of the next cell.
DEPOSIT NEXT
Deposits the contents of the AC switches in
the memory cell specified by the PC. The
C(PC) are then incremented by one. The
C(AC), C(MB), and C(MA) are the same as
for DEPOSIT.
Control States
The POP-4 operates in one of four primary control states during a memory
cycle: Fetch, Defer, Execute, or Break. The next control state is established
at the completion of the current one. All states except Break are deter.
mined by the instructions themselves.
FETCH: A new instruction is obtained when this state occurs. The
contents of the memory cell specified by the PC are placed in the MB,
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