ULA6C001E
The Ferranti Ula6c001e is the customer circuit used in the computers of ZX Spectrum and its some clones, especially the didactic of the gamma.
Ula obsna is "Uncommitted Logic Array", some predecessor of today's CPLD and FPGA. It was a technology developed by Ferranti, whose Sinclair was one of the first users in ZX81 (including all the discrete ZX80 Plus logic plus the NMI generation into the original ZX81 2C158E ULA).
- Sinclair zx81,
- Sinclair ZX Spectrum 16 and Sinclair ZX Spectrum 48 (ULA5C112E, ULA6C001E6, ULA6C001E7)
- Sinclair ZX Spectrum 128+ and Sinclair ZX Spectrum 128 +2 (ULA7K010E5)
A similar implementation of ZX-Spectrum compatible logic is ULA1 in many eastern clones, but it is not a substitute, but only implies similar functionality.
MH6001
In 1989, Tesla Rožnov developed a variant of the ULA perimeter for ZX Spectrum known as MH6001.
Clanek Mr. Drexler in ZXM 2/91 states:
About 2 years ago in Tesle Rožnov managed to construct (more concise expression would be "copying") the perimeter of the ula, which is the basic, so far difficult to replace the heart of the classic ZX Spectra, but also ZXS+ and didactics of gamma. The circuit is marked with MH 6001 and we had the opportunity to test it for a short time. O.K. only worked, only sometimes when the computer was switched on and the screen remained dark, which did not happen with the original ula even once. Since more of these IOs were not available, it could only go about the defect of the sample. The temperature of the housing after long -term operation is comparable to the classic ULA, the lower differences were found in sensitivity in recording programs, the image frame (Border) was moved somewhat more to the left. However, it should be said that similar small differences can be found between the individual types of the original ula. When reading MGF input from address 254, we get 191, which corresponds to newer ULA types. Because of this, some programs, such as slowloader, do not go, fortunately this feature or if you want to remove the error either by adjusting the SW or HW.
Further at the discussion forum OldComp.cz:
A good thing was doing .. I tried to contact a person in O onSemi for a long time, if he had any info about the ULA for ZXS that was supposed to be produced in Tesla Rožnov ... and here is the result:
At that time, I worked on a designed group of digital customer district. (Zio, about 3 people).
We tried to copy the perimeter for a didactic, based on a gate field, which at that time also evolved (not copied) for the ZVT (computing equipment)
First, we made a reverse engineering original ULA, from the micro photo layout (2x2m) we 'we have drawn the logic of wiring. We never did not define the total ULA scheme, it was really a copy of the connection of the gates.
This way of the IO structure was exceptional in our country, we never used it in front of these or then. We have always developed logical customer circuits according to the scheme (keyboard controllers for Zbrojovka Brno, CRC controllers, and multipliers for Hdet computers Zilina .....)
An attempt to develop a copy of the ULA was rather an unofficial action of enthusiasts, without official support and deadlines. As a development after working hours ... the second or 3 Pass began to work a bit in the didactics. Zio did not even have a comprehensive test support at that time, it was tested after encapsulation by inserting into the didactic board. This approach to ZIO development has never been practiced before or after. The didactic then backed away from further cooperation. - Development has never finished. I think they found the channel to get the original ula ..
The development of the 200 -field field was completed, the development of 1000 gate field ...
Josef's health
PS I have a test didactic from that time hidden ..