; GENTEST.ASM
;
; Generate test audio for recording on a cassette. 
;
;    The output of this program is simply the letter"U" (055h) written
;    over and over with a 1.5 character idle period in between each character. 
;    The tape written by this program, in turn, should be read in using
;    the CASTEST.ASM program and the volume output on the cassette player
;    adjusted until the "U" characters are displayed without error.
;
;    To run this program, load GENTEST.HEX into memory using the "Load HEX File"
;    menu option in the Configuration Monitor. Let the tape record idle
;    mark state for about five seconds before running this program from
;    address zero. Record the output of this program for about one minute
;    before stopping the tape.

	org	0		;load and run from address zero
nxtChar	mvi	a,'U'		;send a "U" out the cassette port
	out	7

; Delay 2.5 character times (at 300 baud) = 6917*12us = 83ms

	lxi	d,6917
delay	dcx	d		;5	
	mov	a,d		;5
	ora	e		;4
	jnz	delay		;10
	jmp	nxtChar

	end