DATAMATH  CALCULATOR  MUSEUM

Texas Instruments Compact Computer 40

Date of introduction:  January 6, 1983
 Available March 1983
Display technology:  LCD dot matrix
New price:  $249.95 (MSRP 1983) Display size:  31 (10 + 3)
Size:  5.8" x 9.3" x 1.0"
 148 x 236 x 25 mm3
   
Weight:  19.8 ounces, 560 grams Serial No:  4734905
Batteries:  4*AA Alkaline Date of manufacture:  wk 28 year 1983
AC-Adapter:  AC9201, AC9201/E Origin of manufacture:  USA (ATA)
Precision:  13/14 Integrated circuits:  CPU: TMC70C20 C11002
 ASIC: AMI 1041036
 ROM: HN61256P
 RAM: 3*HM6116LP
 DISPLAY: HD44780A, HD44100
Memories:  6kB RAM, 34kB ROM    
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (US: 2.0M Bytes)

Texas Instruments introduced in January 6, 1983 with the Compact Computer 40 or CC-40 a battery-operated but yet powerful computer based on an 8-bit microcontroller from the TMS7000 family.

The CC-40 was a result of the "Project X" initiated already in Summer 1977 and leading to the development of the failed TI Programmable 88 and Compact Computer 70 aka CC-70, too.

The CC-40 can operate about 200 hours with its disposable alkaline batteries and keeps programs and user data even when powered off for several months. It was priced similar to programmable calculators like the TI-59 or TI-88 and continued the idea of Solid State Software Modules with its integrated Cartridge Port.

The CC-40 introduced with the HEX-BUS a very innovative port to connect peripherals in a daisy-chain mode very similar to the USB port released more than a decade later. One of the peripherals planned for the Compact Computer family was the HX-2000 Wafertape, a continuous loop tape drive developed by Exatron and known as Stringy Floppy.

The HX-2000 Wafertape had major reliability issue and was never released to the market. Without any other means for mass storage of programs and data, Texas Instruments developed consequently the Compact Computer 40 Plus with an integrated port to connect a cassette audio recorder to save programs or data files on tape.

Texas Instruments dropped out of the home computer market in March 1984 - after selling more than 2.5 million of the famous TI-99/4A - and production of the CC-40 was ceased immediately after. The CC-40 Plus never made it to the market and only a few prototypes survived.

It took another two years before Texas Instruments introduced with the TI-74 BASICALC and TI-95 PROCALC the successors of both the TI-88 and CC-40. Five different members of the Compact Computer System are known, only two of them where actually released:

Part

Name / Description

MSRP (1983)

Status

CC-40 2K Prototype of CC-40 with 2k RAM and first design of the Expansion Cartridge t.b.d. Prototype
CC-40 6K Standard Version $249.95 Series
CC-40 18K Integrated Memory Expansion t.b.d. Series
CC-40 Plus Integrated cassette port t.b.d. Prototype
CC-70 8-line Display and Multi-Port Expansion Cartridge t.b.d. Mockup

The Compact Computer 40 uses the proprietary HEX-BUS to connect peripherals, eight different products like printers, plotters and even a serial interface were available or planned:

Part

Name / Description

MSRP (1983)

Status

HX-1000 Printer / Plotter 4 colors $199.95 Series
HX-1010 Printer 80 (Thermal ribbon) $249.95 Series
HX-1100 Video Interface $99.95 Prototype
HX-2000 Wafertape Digital Tape Drive $139.95 Prototype
HX-3000 RS-232 Interface $99.95 Series
HX-3000/P RS-232 + Parallel Interface $124.95 Series
HX-3100 Data Modem $99.95 Series
HX-5102 Disk Drive/Controller t.b.d. Prototype

The integrated cartridge port of the Compact Computer 40 supports not only pre-programmed Solid State Software Modules like the TI-59, but allows RAM based Memory Expansions and UV EPROM Program Cartridges. Today we know twelve different cartridges but not all of them were released as of March 1984 when the complete Compact Computer portfolio was discontinued:

Part

Name / Description

MSRP (1983)

ROM-Code

Status

SS-1000 16k RAM Memory Expansion $149.95 n.a. Series
SS-1001 Pascal module $59.95 n.a. Series
SS-2000 8k RAM Memory Expansion with Li-Backup Battery $99.95 n.a. Series
SS-3004 Memo Processor for Data Communications $69.95 1500387
4000
Series
SS-3006 Finance module $59.95 1500387
1100
Series
SS-3007 Advanced Electrical Engineering module $59.95 1500387
1202
Series
SS-3008 Statistics module $59.95 1500387
xxxx
Series
SS-3009 Mathematics module $59.95 1500387
1003
Series
SS-3024 Games I module $39.95 1500387
xxxx
Series
SS-4002 Editor/Assembler (Requires Wafertape or Disk Drive/Controller) $124.95 1500387
9100
Prototype
8K-EPROM 8k UV EPROM Program Cartridge t.b.d. n.a. Prototype
16K-EPROM 16k UV EPROM Program Cartridge t.b.d. n.a. Prototype

Dismantling the featured Compact Computer 40 manufactured in July 1983 by Texas Instruments in their Abilene, TX facility, reveals a neat design with just two printed circuit boards (PCBs). The Main-PCB illustrates a design with four main building blocks:

CPU (Central processing Unit): The Texas Instruments TMC70C20 microcontroller is a member of the TMS7000 family manufactured in CMOS technology. The original design of the TMS7000 series was introduced in 1981 as an 8-bit extension of the TMS1000 Family to compete with already well established Intel i8051, Motorola M6801, and Zilog Z8 products. The first chips sported 128 bytes of on-chip RAM (Random Access Memory) and either 2k Bytes or 4k Bytes of ROM (Read Only Memory). The featured CC-40 sports with the TMX70C20 with ROM-Code C11002 a very early prototype of the TMC70C20, both equipped with 2k Bytes of ROM. Read more about TI Standard Symbolization used in the Eighties with ICs manufactured in a metal–oxide–semiconductor (MOS) process. Interesting to observe that the microcontroller of the Compact Computer System CC-40 displays ROM-Code C11002, while the HX-2000 Wafertape sports with ROM-Code L11001.

ROM (Read-Only Memory): The ROM contains the operating system of the calculator or computer. The first products on the market used mask-programmable ROM, the program was stored already during the production of the Integrated Circuit. Later calculators changed to Flash ROM, a technology allowing the programming of the software during the final production stage of the calculator. With the TI-83 Plus and all later graphing calculators from Texas Instruments even the user was able to reprogram the operating system.

The HN61256P ROM of this CC-40 was manufactured by Hitachi and offers a capacity of 32k Bytes for the BASIC interpreter.

RAM (Random Access Memory): The RAM is used as data memory and is used to store both variables, user programs and intermediate results. This CC-40 makes use of three HM6116 manufactured by Hitachi, Japan with 2k Bytes capacity, each. The total capacity of the memory is 6k Bytes using three HM6116LP chips, later versions of the CC-40 featured 18k Bytes of memory using one HM6116LP and two HM6264LP (8k Bytes) chips.

ASIC
: The CC-40 uses an AMI 1041036 application-specific integrated circuit (ASIC), it contains the "glue logic" to connect the memories, keyboard and LC-Display to the TMC70C20 microcontroller and integrates the Hex-Bus Peripheral port. With the Hitachi HN61256P used with the CC-40 and its Solid State Software Cartridges featuring a rather long access time of up to 3.5 us and the TMC70C20 CPU lacking a "wait-state" mechanism, incorporates the ASIC additional circuitry to slow down the CPU clock cycle while accessing the ROM chips. The TMC70C46 chip used with the TI-74 BASICALC and TI-95 PROCALC integrated all these features and dropped the additional ASIC found with the CC-40 design completely.

The front view of the second PCB shows the dot matrix LC-Display with 31 characters width and the contacts of the 61 keys of the keyboard. The back of the second PCB reveals the control and driver electronics for the LC-Display:

DISPLAY: The CC-40 uses the Hitachi HD44780 LCD Controller and one additional Hitachi HD44100 LC Driver. The HD44780 contains the character generator for 208 characters in a 5x8 dot matrix, 32 characters in a 5x10 font, RAM for a maximum of 80 characters and the driver electronics for 16 characters. The HD44100 adds an additional 40 segment drivers for the remaining characters.


horizontal rule

If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, December 5, 2001. No reprints without written permission.