HP48 Sources Page.

This program tests your "speed". Start the program and then press any key and release it as fast as you can and see how long you held it down. My record is somewhere around 40. Turning the screen off during the loop lets the program run slightly faster.

Key


Size 87.5 Checksum: # B7C0h
::
 CODE
	GOSBVL	=SAVPTR		save internal pointers
	GOSBVL	=DisableIntr	turn off all interrupts
	GOSBVL	=DispOff	turn off the screen
	B=0	A		initialize the counter to zero

* wait until you stop pressing the key

waitkeyup
	LC(3)	#1FF		load keyboard rows
	OUT=C			| set the OUT register
	GOSBVL	=CINRTN		| read the IN register
	LA(5)	#803F		| load mask
	A=A&C	A		| mask out keys
	?A#0	A		any keys down?
	GOYES	waitkeyup	yes, wait again

* wait until you start pressing the key

wait4key
	LC(3)	#1FF		load keyboard rows
	OUT=C			| set the OUT register
	GOSBVL	=CINRTN		| read the IN register
	LA(5)	#803F		| load mask
	A=A&C	A		| mask out keys
	?A=0	A		any keys down?
	GOYES	wait4key	no, wait again

* now start counting as you hold down the key

count
	B=B+1	A		add one
	LC(3)	#1FF		load keyboard rows
	OUT=C			| set the OUT register
	GOSBVL	=CINRTN		| read the IN register
	LA(5)	#803F		| load mask
	A=A&C	A		| mask out keys
	?A#0	A		what, are you still pressing the key?
	GOYES	count		yes, continue adding

	A=B	A		prepare to push number
	GOSBVL	=DispOn		turn on the display
	GOSBVL	=AllowIntr	turn on the interrupts
	GOVLNG	=PUSH#ALOOP	push the number to the stack and restart rpl
ENDCODE
 UNCOERCE			(convert it to a float)
;