		HP21xx MONITOR
		==============

This is a monitor for the HP21xx series.
It provides for the manipulation of memory and direct exercising of I/O devices.

A default interrupt handler is installed for all interrupts.
This handler will display a message if an interrupt is received.

An additional module provides control of the 13181-controller-based magnetic tape drives.

This monitor is formed from two assemblies, the "sys" assembly is a lower level interface 
providing some common services, the "monitor" assembly provides the user-level command parsing and display.

The file monitor.abs contains both assemblies, combined into one load file.

2004:		created / bhilpert
2014 Nov:	modified for assembly by hp21asm / bh


============================================================================================================

Command Summary:
----------------

m*emory [<addr> [<count>]]	display memory, <count> defaults to 1,
				current address and count are set.

wr*ite <value>			write <value> to memory location of current address,
				increment current address and set count to 1.

fill <addr> [<count> [<value>]]	fill memory, <count> defaults to 1, <value> defaults to 0,
				current address and count are set.

copy <srcAddr> <dstAddr> [<count>]	copy memory, <count> defaults to 1,
					current address and count are set to destination.

j*ump [<address>]		jump to address, restart if no address.

bbl				jump to the Binary Boot Loader.
				(expects the bbl in upper mem, may mess up other boot loaders)

p*aging [0/1]			turn page pausing on (1) or off (0), default on.

?				display a list of the command keywords.

rate				increment 32-bit counter for one second interval.

char*acters [<terminationChar>]	read bytes from the console until <terminationChar> seen,
				then display the bytes in octal form.
				<terminationChar> defaults to '.' (period).

d*evice [<selectCode>]		set or display current device.
in*put				display device input register and flag.
out*put <value>			output <value> to device channel.
cs*et				set device control bit.
cc*lear				clear device control bit.
fs*et				set device flag bit.
fc*lear				clear device flag bit.

mt				display the mag tape status.
mt r*rf				read a record from tape, using internal address and count.
mt w*cc				write a record to tape, using current address and count.
mt g*ap				write a gap.
mt f*sr				forward space record.
mt b*sr				backward space record.
mt wfm				write a file mark.
mt gwm				write a gap and a file mark.
mt fsf				forward space file.
mt bsf				backward space file.
mt rew				rewind.
mt rwo				rewind and offline.
mt c*lr				clear controller.
mt sel<n>			select unit, <n>=0,1,2,3.
mt readfile [0/1]		read records until EOF mark, 0 suppresses data display.
mt ?				display a list of the mag tape command keywords.
