I decided to design a new front panel with more 'gears'.
• Subproject LCDs mostly finished.
• Subproject IR-Keyboard mostly finished.


Data and Address Register Boards

I have ordered the address and data registers boards from LeitOn. Again the quality is not as good as from PCB-Pool, the boards are slightly bent. Both boards are now finished:
K1-16/16 Data Registers Board
K1-16/16 Address Registers Board
Seemingly some companies expect a great economical success for my groundbreaking CPU design:



2009-10-05: CadSoft is bought by Premier Farnell plc.
I have ordered the ALU PCB from LeitOn.
It is of lower quality than the board from PCB-Pool.
K1-16/16 Arithmetic/Logic Unit


Front panel finished

I finished and manufactured the front panel PCB. It provides 3 clock sources for demonstrations and debugging. It is single-sided, so i could etch it at home. I have tested my mental rugginess and designed the front panel in Open Office.
2009-09-27: Today we had elections in Germany. Of course i did vote, though, there is not much to choose between ...


The Majority Gate

After a long while I resumed work on the Arithmetic/Logic Unit. I wired up a test circuit for the 3-resistor majority gate, which i use in the ALU for the joined AND and OR functions. I was lucky and the gate worked as expected. Dieter Müller has written an article about the majority gate and it's use for ALU design. Website now offline (2010) and email address invalid. I don't know what has happened to him :-/


Working on the compiler

Working on the compiler for user-space (as opposed to microcode) programs. It seems it's gonnabe a compiler, not an assembler, with c-like syntax and some c++ goodies. Finally i got stuck. Using a non-typed script language to write a compiler has it's disadvantages too.


Working on microcode

Working on the microcode and microcode assembler.The microcode is organized in 2 planes of 16k * 24-bit codes. There is a 1-instruction pipeline which imposes a 1-instruction latency on code branching: In every microcode instruction a flag is selected. This flag is tested at the end of the previous instruction and determines from which code plane the next instruction is read. The assembler takes care for the most of this brain hazzard.


The Control Unit


Production of the first board by PCB-Pool (voucher). It is the control unit, which is abbreviated as "SSW" for German "Schrittschaltwerk".


I'm in the Homebuilt CPU Webring.
The Control Unit is finished:
K1-16/16 Control Unit


EagleCAD certainly has it's quirks.

EagleCAD certainly has it's quirks.