Tektronix Phaser 300X user manual Parallel port signal descriptions

Technical Notes A

Parallel port

The printer has a standard unidirectional, byte-wide parallel, synchronous port. When you use the parallel port, be sure to type this command at the PC (if LPT1 is not available, use LPT2):

MODE LPT1:,,P

The table shows the parallel port’s connected pins. Other pins are not connected. Signal names ending with a dash (–) are asserted low.

Parallel port signal descriptions

Signal name	Pin #	Return	Signal	Description
		pin	source
DSTRB–	1	19	Host	Pulsed low for .5 microseconds
				minimum; clocks data into printer
DATA1	2	20	Host	Positive true data input
DATA2	3	21	Host	Positive true data input
DATA3	4	22	Host	Positive true data input
DATA4	5	23	Host	Positive true data input
DATA5	6	24	Host	Positive true data input
DATA6	7	25	Host	Positive true data input
DATA7	8	26	Host	Positive true data input
DATA8	9	27	Host	Positive true data input
ACK–	10	28	Printer	Data acknowledge pulsed low for
				3-4 microseconds; ends bus
				transaction
BUSY	11	29	Printer	Positive true = cannot accept data
PE	12	—	Printer	Positive true = out of paper
SLCT	13	—	Printer	Positive true = printer selected
INPRIME–	31	30	Host	Negative true = printer port reset
FAULT-	32	—	Printer	Negative true = printer fault
				indicator
Frame Gnd	—	17	Printer	Frame ground
SGnd	—	14,16,33	Printer	Signal ground

User Manual A-5