Documentation for Martel MCP9821X-055
parallel port Thermal Printer
available from Omni Systems Associates
on the ebay store

power: 8V DC @ 4.0 Amps Max, - tip, + sleeve

paper width: 2 ¼ inch, 58mm
2 ⅛ inch max roll diameter

DB15 to DB25 Pinout & Signals

(PC standard)
direction signal
1 1 /strobe
2 2 Data 0
3 3 Data 1
4 4 Data 2
5 5 Data 3
6 6 Data 4
7 7 Data 5
8 8 Data 6
9 9 Data 7
10 10 /Ack
11 11 Busy
12 12 Paper Out
13 13 Select
14 autof
14 15 Error
16 /init
17 /select
15 18 19 20 21
22 23 24 25

→ To Printer
← From Printer
Wikipedia: PC parallel port
more details of the Centronics signals

Documentation from Omni Systems Associates:
Martel Instruments
14892 Trojan Cir
Huntington Bch CA 92647
Tel: 800-652-5667
Fax: 714-892-0096,74776.0.html

Small Thermal Printer - For Arduino, Raspberry Pi, PIC, PC? MARTEL MCP9821X-055
$45.00 Buy It Now + $9.50 Shipping + $10 power supply

Seller Notes: Units are removed from laboratory test equipment,
    some units are new, most are very lightly used, all are in good working order, inspected and tested.
Brand: Martel
Output Type: Black & White
Technology: Thermal
Connectivity: Parallel (IEEE 1284)
Model: MCP9821X
Printer Type: Point of Sale Printer
Country/Region of Manufacture: United Kingdom

Martel MCP9821X Parallel Thermal Printer.
These units have a non standard 15 pin connector (Female DB15HD - Like a VGA connector),
but use standard parallel signaling and the pin-out will be provided
as well as a diagram for DB25 to DB15 adapter cable, which can also be purchased ($29) separately.
The printer requires 8 data bits and a strobe signal, handshake is by ack/busy (standard Centronics/PC parallel).

The printers work very nicely connected to an Arduino or compatible micro-controller
using the Parallel Printer Sketch on the Arduino.CC forums.
The hookup is very straightforward and a male DB15HD connector
(to make your own cable for Arduino or other microcontroller)
and cable diagram will be provided with the printer if requested when purchased.

Printer requires 8V DC at 4A which is similar to the input voltage for Arduino (7-12V DC)
and the same 8V DC power supply can be used to power the Arduino and the printer.
Power supplies are not included but are available separately - view the other items we have for sale.
If power supply is purchased with printer the cost will be just $10
and we will ship them together with no additional shipping cost for the power supply.
Just buy the printer and then make an offer of $5.05 for the power supply
($5.05 + $4.95 shipping = $10 total for the power supply - to be shipped with the printer).

Units are removed from laboratory test equipment,
some units are new, most are very lightly used,
all are in good working order, inspected and tested.

The printer can print at 12, 16, 24, 32 and 48 characters per line on standard 58mm wide thermal paper.
The printers can also print bar codes and a variety of symbols and graphics characters (see pictures of test prints).

With appropriate paper rolls the printers can also be used as POS printer (Point Of Sale),
credit card slip printer, or label printer.
Almost any type of thermal roll paper can be used (with some variation in the quality of printout depending on the paper).
We have tested the printer with standard thermal paper rolls as used in calculators
and credit card machines as well as with Dymo type thermal labels and others - all worked well.
MCP9800 series printers [serial interface but the same print mechanism & housing]