AudioQuest M-27 specifications Printer Setup, Extending Battery Life

Printer Setup

Serial Printer Output

The serial printer output is RS-232-C compatible. It sends data in ASCII code at 300, 600, 1200, or 2400 Baud.

The data is sent asynchronously. The Data Set Ready line is checked before sending a character. Each character consists of 11 bits made up of a start bit, 8 ASCII character bits, and 2 stop bits. Each line is terminated by a line feed and/or carriage return characters.

Printer Switch Setup

The internal switches must be set to agree with the printer. Switch 3 controls the printer (see Internal Switch Settings). Positions 1 and 2 should normally be off.

Positions 3 and 4 are normally on (graph and text).

Positions 5 and 6 control last 2 characters/line. Many printers work if both are on. Positions 7 and 8 control baud rate.

7 on and 8 on = 300 baud

7 on and 8 off = 600 baud

7 off and 8 on = 1200 baud

7 off and 8 off = 2400 baud

Parallel Printer Setup

When set to parallel the M-27 is compatible with most Centronic compatible printers. The M-27 sets up 8 data lines, if the Busy line is not high it sends a Strobe pulse.

If the Busy line stays high for more than a few seconds, the M-27 will cancel the printout. Printer Switch Setup

See Internal Switch Settings.

Positions 1 and 2 are normally ON for parallel printers.

Positions 3 and 4 are normally ON (graph and text).

Positions 5 and 6 control the last 2 characters/line. Most printers work with both ON. Positions 7 and 8 are undefined for parallel.

Computer Connections

The M-27 can send its data to personal computers over the RS-232 port. In general, the computer and M-27 are set up similar to a serial printer. The computer is programmed to be a data terminal and the data is read into the computer. If the data is saved in an ASCII file, it may be edited with a word processor program.

Consult the Quest factory for hints on using the M-27 with specific computers.

Printer Pinouts
The 20-pin connector is numbered from right to left starting with 1 in the upper right corner, 2 in
the lower right corner, and 20 in the lower left corner when looking at the M-27.
	Serial	Parallel
Pin 1	Data Signal	Strobe	+ 5 to +5 minus the
			battery voltage, 300 ohm
			impedance
Pin 3	--	Data 0 Output of HC CMOS driver
Pin 5	--	Data 1 Output of HC CMOS driver
Pin 7	--	Data 2 Output of HC CMOS driver
Pin 9	--	Data 3 Output of HC CMOS driver
Pin 11	--	Data 4 Output of HC CMOS driver
Pin 13	--	Data 5 Output of HC CMOS driver
Pin 15	--	Data 6 Output of HC CMOS driver
Pin 17	--	Data 7 Output of HC CMOS driver
Pin 20	DSR	Busy	Input > +3 volts = 1
Pins 2, 4, 6, 8,	Ground		Input < +1 volts = 0
10, 12
Pin 14	External battery minus
Pin 16	External battery plus
Pin 18, 19	No connection

EXTENDING BATTERY LIFE

Since the M-27 stores data even when it is turned off, the battery should be removed if it is not to be used for a few days.