|  | DATAMATH CALCULATOR MUSEUM | 
Texas Instruments PC-800 Printer
| Date of introduction: | Never (Announced: May 26, 1982 Cancelled: September 10, 1982) | Display technology: | |
| New price: | MSRP: $185.00 | Display size: | |
| Size: | 6.5" x 10.0" x 2.7" 165 x 254 x 68 mm3 | Printer technology: | Thermal TP-xxxxx | 
| Weight: | 50.8 ounces, 1,442 grams | Serial No: | 1235363 | 
| Batteries: | Date of manufacture: | wk 34 year 1982 | |
| AC-Adapter: | 120 V or 240 V or DC | Origin of manufacture: | USA (ATA) | 
| Precision: | Integrated circuits: | TMS1000/CD8000B, 
	TMS1300/CD8020A, 
	SN77203, LM393P, 3xULN2002A | |
| Memories: | |||
| Program steps: | Courtesy of: | Joerg Woerner | 


 The
PC-800 Printer is a dot-matrix thermal printer designed for use with the 
TI-88 Programmable. It connects to the TI-88 through a 2-pin 
Peripheral I/O connector. A second Peripheral I/O connector on the back of the 
PC-800 allows to connect another device like the CA-800 
Cassette Interface to the TI-88.
The
PC-800 Printer is a dot-matrix thermal printer designed for use with the 
TI-88 Programmable. It connects to the TI-88 through a 2-pin 
Peripheral I/O connector. A second Peripheral I/O connector on the back of the 
PC-800 allows to connect another device like the CA-800 
Cassette Interface to the TI-88.
Printer Control of TI-88 Programmable:
| • Print the contents of the display at any time • Print alphanumeric prompts, operating instructions, and messages • Print program input and output • Print the contents of program or data memory • Print all labels used in a program • Print OP code and flag definitions, calculator settings, nd alpha entry positions • Print tracings of keyboard calculations and program execution showing each function executed with its result | 
The PC-800 printer operates by moving an electronic print-head across a special heat-sensitive paper. Characters are formed on the paper from small dots produced by heated elements on the print-head.
 Dismantling this PC-800 
manufactured by Texas Instruments in August 1982 in their Abilene, Texas 
facility, reveals a design with a complexity similar to the 
PC-100C and PC-200 
printers utilizing two microcontrollers 
TMS1000/CD8000 and TMS1300/CD8020, a SN77203 Voltage 
Controller chip and three ULN2002A arrays with seven NPN Darlington transistors, 
each.
Dismantling this PC-800 
manufactured by Texas Instruments in August 1982 in their Abilene, Texas 
facility, reveals a design with a complexity similar to the 
PC-100C and PC-200 
printers utilizing two microcontrollers 
TMS1000/CD8000 and TMS1300/CD8020, a SN77203 Voltage 
Controller chip and three ULN2002A arrays with seven NPN Darlington transistors, 
each.
 The two microcontrollers with Custom Design Software 
TMS1000/CD8000 Revision B and 
TMS1300/CD8020 Revision A are in different stages of evolution, the CD8020 
component uses already the final chip package while the CD8000 still uses a 
prototype package. The SN77203 is known from the
TI-88 Schematics Diagram, it converts 
a single-cell battery (1.2 Volts - 1.5 Volts) to two independent power supplies, 
one adjustable for the LC-Display through a Serial I/O pin and one fixed for the 
main electronics.
The two microcontrollers with Custom Design Software 
TMS1000/CD8000 Revision B and 
TMS1300/CD8020 Revision A are in different stages of evolution, the CD8020 
component uses already the final chip package while the CD8000 still uses a 
prototype package. The SN77203 is known from the
TI-88 Schematics Diagram, it converts 
a single-cell battery (1.2 Volts - 1.5 Volts) to two independent power supplies, 
one adjustable for the LC-Display through a Serial I/O pin and one fixed for the 
main electronics.
 Please 
notice the additional diodes with this PC-800 Printer compared to a 
PC-800 EVT 
(Engineering Validation Test) manufactured a few month earlier. Learn more about 
similar modifications discovered with the TI-88 PVT 2 
(Production Validation Test 2).
Please 
notice the additional diodes with this PC-800 Printer compared to a 
PC-800 EVT 
(Engineering Validation Test) manufactured a few month earlier. Learn more about 
similar modifications discovered with the TI-88 PVT 2 
(Production Validation Test 2).
 The 
PC-800 Printer can be operated by either an integrated AC adapter with 120/240 
Volts (fixe-mounted power cord) or an external DC adapter (connector on the rear 
next to the two Peripheral I/O connectors.
The 
PC-800 Printer can be operated by either an integrated AC adapter with 120/240 
Volts (fixe-mounted power cord) or an external DC adapter (connector on the rear 
next to the two Peripheral I/O connectors.
Printer paper:
 
The thermal paper used with this printer (Kanzaki Paper 
KPB-53Z-48 1.97" wide and 85 Feet length) was discontinued long time ago.
	 Don't connect a CA-800 Cassette Interface or a PC-800 Printer to TI-88 calculators without the Diode-Modification!
Don't connect a CA-800 Cassette Interface or a PC-800 Printer to TI-88 calculators without the Diode-Modification!
 
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, October 14, 2019. No reprints without written permission.