:: 4K Memory Checkerboard
echof "** PDP-8: 4K Memory Checkerboard: "
:: Normally, these should run until the user was satisfied and 
:: stopped them.  But we're not looking for hardware failures,
:: so hopefully a single pass of each suffices.
:: Start with low version
load -r diags/maindec-08-d1l1-pm
:: Patch address 0072 with HLT. Otherwise the test loops
:: indefinitely.
dep 0030 7402
# Set switches:
# 0100	Straight-8
# 0101	PDP-8/I
dep sr 0101
# Need flags clear?
#reset all
go -q 0005
if (PC != 00031) echof "MAINDEC-08-D1L1 failed."; exit 1
:: Now run high version
load diags/maindec-08-d1l2-pb
:: Patch address 7451 with HLT. Otherwise the test loops
:: indefinitely.
dep 7472 7402
go -q 7430
if (PC != 07473) echof "MAINDEC-08-D1L2 failed."; exit 1
echof "** PDP-8: 4K Memory Checkerboard passed"