The MicroTim is a Romanian unlicenced ZX Spectrum clone. It is one of the first models made at the factory in Timisoara, western Romania in the early 1980s. MicroTim stands for "Micro" and "TIMisoara". It was designed at Polytehnica University from Timisoara (former TUT - Technical University of Timisoara, former IPTVT - "Traian Vuia" Polytechnical Institute), but its large scale fabrication started and continued at the Fabrica de Memorii Timisoara (the Computer Memory Factory).
When the ZX Spectrum appeared in the early 80's, three unlicenced Romanian clones were developped almost independently. These were developped in three main university centres from Timisoara, called initially microTim, and then TimS (from TIMisoara and Spectrum), Cluj-Napoca called Prae (which means "beginning" in latin) and Bucharest called aMIC (translated as "aSMALL"). These were developped using a combination of the "black box" principle and illegally obtained desings. The "Black Box " approach was widely developped and used in Eastern Block for developping electronic devices. The same principle was used in Eastern Germany to make the best PC in the east called "Robotron". Unformally, "Black Box" means replacing a chip or a groups of chips that I do not know (or do not have) with another group that has same input and output signals.
The Cluj group dissapeared quite quickly, but Timisoara and Bucharest continued making spectrum based computers until early 1990s. Timisoara choose to further integrate and extend the model (as Sinclar did). The main designer behind TimS is eng. Dumitru Panescu who reached quite a mastery skill in integrating spectrum designs. His last prototype of TimS (it was never produced) integrated all spectrum firmware into one computer including a CP/M option. At start-up the user would select by pressing a key what does he or she wants to use.
It has an original & small keyboard (40 keys) with statements and functions labeled next to the keys, like on the ZX Spectrum. The system is powered by an external power supply.
Further information from Adrian Dragodan:
The prototype was called SpecTim. AFAIK, it was never industrially produced.
TIM-S was the first production model, dual speed (3.5 and 6 Mhz) were available, using a Z80B.
It had a flat, sensorial keyboard (In the later models it was a normal kbd, all the ones produced and labeled DataTIM were TIM-S's with normal keyboard).
MicroTIM was the later, cost-reduced version. First issues had a numeric keypad, but the keyboard was really lousy, hardly usable for editing. The latest issues of Microtim included a better keyboard.
Differences btw TIM-S and MicroTIM:
- Reduced number of IC's: TIM-S: about 80, MicroTIM: about 50
- TIM-S: 6 Mhz mode, 80 KB RAM, 16 KB ROM
- Microtim: only 3.5 Mhz, 64 KB RAM, 16 KB ROM
- In both models the ROM was copied into RAM, so it was possible to load other ROM from tape
- In TIM-S, the video memory was doubled.
About the cases, there were MicroTIM's with numerical keypad. All used that same case, except some versions of M-TIM+, that had a separated keyboard and internal PSU.
M-TIM+ was not functionally different from earlier M-Tim's and my M-Tims+ have the case of M-TIM.