After the TK80, TK82 and TK83 the TK85 was the last ZX-81 compatible machine Microdigital produced.
However it wasn't only a simple copy of the ZX-81 but featured several useful enhancements. Its rubber keyboard and case were similar to the Spectrum's and were much more pactical for intensive use. The 10 KB ROM held an improved version of the Sinclair's Basic with strings management and editing facility, as well as some primitive graphic commands.
Several additional routines allowed to record tape programs up to 4200 bits per second, manage a joystick interface and the built-in three-voice sound generator.
Thanks to the TK85, Microdigital started to lead the Brazilian home computer market, front of Sinclair and its US branch, Timex.
Thanks to Joao Roberto for most of the pictures and information.
Please consider donating your old computer / videogame system to Old-Computers.com or one of our partners from anywhere in the world (Europe, America, Asia, etc.).
I Still have one with a thermal printer old K7 player and small black $ white tv.
Thursday 4th June 2015
Carlos Deabreu (usa)
It''s a really beautiful desing. A cool clone of ZX81.
This was my first computer!!!! My dad bought it for me when I turned 16 (I was living in Argentina at the time). I learned how to program in Basic on this little computer. Great memories! :)
Friday 3rd September 2010
Rey D (USA)
NAME
TK-85
MANUFACTURER
Microdigital
TYPE
Home Computer
ORIGIN
Brazil
YEAR
1983
END OF PRODUCTION
Unknown
BUILT IN LANGUAGE
Improved version of the ZX81 Basic
KEYBOARD
40-key QWERTY rubber keyboard with up to 5 function per key
CPU
Zilog Z80 A
SPEED
3.25 MHz
RAM
16 KB up to 48 KB
ROM
10 KB
TEXT MODES
32 columns x 24 lines
GRAPHIC MODES
64 x 44 dots
COLORS
Monochrome
SIZE / WEIGHT
23 (W) x 14 (D) x 3 (H) cm / 500g
I/O PORTS
Expansion port, Tape-recorder, RF video out, Joystick