The TK-80 (Training Kit μCOM-80) was an 8080-based single-board computer kit developed by Nippon Electric Company (NEC) in 1976. It was originally developed for engineers who considered using the μCOM-80 family in their product. It was successful among hobbyists in late 1970s in Japan, due to its reasonable price and an expensive computer terminal not being required.
|Developer||Tomio Goto, Akira Kato|
|Release date||August 3, 1976|
(equivalent to ¥151,735 in 2019)
|Units sold||17,000 (As of October 1977)|
26,000 (As of October 1978)
|CPU||NEC μPD8080A 2.048 MHz|
|Memory||ROM 768 bytes、RAM 512 bytes|
|Display||8 hexadecimal digits; 7-segment display|
|Connectivity||110 bps Serial I/O, 3 × 8 bits Parallel I/O|
|Power||DC +5V 1.0 A, +12V 0.15 A|
|Dimensions||310(W) × 180(D) mm|
In February 1976, NEC formed the Microcomputer Sales section in the Integrated Circuit division, and began to provide development environments for their microprocessors. However, they visited customers and explained, but it was difficult for them to understand how to use a microprocessor. At the same time, NEC received an order from a laboratory in the Yokosuka Communication Institute of NTT that they wanted an educational microcomputer product for their new employees. Tomio Gotō (後藤 富雄), a member of the section, proposed to his manager Kazuya Watanabe (渡辺 和也) developing an educational kit.
Goto mainly designed the TK-80, and Akira Katō (加藤 明) did the detailed design work. Goto got an idea from a photo of the KIM-1. The KIM-1 can monitor and show the current address by the software, but the display disappers when the CPU is hanging. The TK-80 has the Dynamic Display using the 555 timer IC and interrupt the CPU, it can always show the current address. In addition, the TK-80 has a CMOS battery. He decided to document its manual with a circuit diagram and assembly code of the debug monitor, influenced by the PDP-8 which was an open architecture.
The TK-80 came out on August 3, 1976. It was priced at 88,500 yen, an engineer's section manager could approve at that time. NEC had opened a support center (Bit-INN) at the Akihabara Radio Kaikan on September 13, 1976. They found many machines were sold to not only electrical engineers but also businessmen, hobbyists and students. The TK-80 was sold more than 2000 units per month, despite 200 units expected.
Soon after its success, other Japanese microprocessor manufacturers developed an evaluation kit for their microprocessor. Power supplies and other peripherals came out from third parties. Watanabe and his members wrote an introductory book Mi-com Introduction (マイコン入門) in July 1977, it became very popular and sold more than 200,000 copies. Also, some computer magazines were founded, the ASCII, the I/O, the Monthly Mi-com (月刊マイコン) and the RAM.
In Japan, the Altair 8800 was sold in 1975, but not successful due to its high brokerage fee. Neither the Apple II nor the Commodore PET. Single-board computers had been popular until the successor PC-8001 came out in 1979.
The TK-80E was a cost-reduced version priced at 67,000 yen, introduced in December 1977. It contained the NEC μPD8080AF (2 MHz), fully compatible with the Intel 8080A. (Original Intel 8080A has a bug in the BCD adjustment. The μPD8080A doesn't.). Other specifications included 768 B (Max. Up to 1 KB expandable) of ROM, and 512 B (Max. Up to 1 KB expandable) of RAM.
The TK-85 was introduced in May 1980 and was the successor to the TK-80E. It contained the μPD8085AC processor (2.4576 MHz) and has a system configuration that is considered to some extent for compatibility with the TK-80. Other specifications included 2 KB (Max. Up to 8 KB expandable) of ROM, 1 KB of RAM, while the board size was 310 × 220 mm. It supported BASIC.
- μCOM-80トレーニング・キット TK-80E/80ユーザーズ・マニアル [μCOM-80 Training Kit TK-80E/80 User's Manual] (in Japanese), 日本電気株式会社 (NEC), IEM-560D
- 大内, 淳義 (1977). マイコン入門 [Mi-com Introduction] (in Japanese). 広済堂出版.
- 関口, 和一 (2000). パソコン革命の旗手たち (in Japanese). 日本経済新聞社. pp. 35–39. ISBN 4-532-16331-5.
- 太田, 行生 (1983). パソコン誕生 (in Japanese). 日本電気文化センター. pp. 20–35. ISBN 4-930916-11-9.
- 日本電気社史編纂室 (2001-12-25). 日本電気株式会社百年史 (in Japanese). NEC. p. 651.
- 塩田, 紳二 (1998). "国産銘機列伝：開発者インタビュー「オープンの発想はPDP-8から学んだ―TK-80開発者、後藤氏に聞く」". ASCII (in Japanese). ASCII Corporation. 22 (5): 314. ISSN 0386-5428.
- 日本電気社史編纂室 (2001-12-25). 日本電気株式会社百年史 (in Japanese). NEC. p. 263.
- 塩田, 紳二 (1998). "国産銘機列伝：History「マイコンと呼ばれていた頃」". ASCII (in Japanese). ASCII Corporation. 22 (5): 312–313. ISSN 0386-5428.
- "パーソナル・コンピュータ 新製品ガイド". ASCII (in Japanese). ASCII Corporation. 2 (11): 39. 1978. ISSN 0386-5428.
- 加藤, 明 (2011-06-01). "J-STAGE : 電子情報通信学会 通信ソサイエティマガジン : Vol. 2010 No. 15 : PC-8001の開発" (PDF) (in Japanese). 電子情報通信学会. Retrieved 2016-11-07.
|Wikimedia Commons has media related to NEC TK-80.|
- "TK 80 : OLD-COMPUTERS.COM : The Museum". Retrieved 2016-11-07.
- "TK-80-Computer Museum:". Information Processing Society of Japan. Retrieved 2016-11-07.
- "Remembrance of TK - 80: TK - 80 BS BASIC Station". Studio RUM blog. Retrieved 2018-11-02. (Japanese language)
- "Specification of TK-80 / 80E (from the catalog of the time)". Denno/Dynamic Museum. Retrieved 2018-11-02. (Japanese language. Photos & overview plus pages for TK-80BS & COMPO BS/80.)
- "IC Collection entry for TK-80 models". IC Collection. Retrieved 2018-11-02. (Japanese language. Photos for TK-80 & detailed overview for TK-80 models.)
- "Akademeia entry for TK-80BS". Security Akademeia. Retrieved 2018-11-02. (Japanese language. Photos & overview for TK-80BS (BASIC STATION).)
- "Funky Goods entry for TK-85". Funky Goods. Retrieved 2018-11-02. (Japanese language. Photos & overview for TK-85, and specifications comparison chart with TK-80.)
- "IC Collection entry for TK-85". IC Collection. Retrieved 2018-11-02. (Japanese language. Photos & overview for TK-85.)