Computer organization – Geronimo/370

Retro Z80 computer (11) – (dis)Assembler

Posted on2022-12-061 Comment

At first, on my retro Z80 (RC2014) computer, I was using the assembler that came with CP/M, named ASM. Later on, looking for the Z80 block transfer instructions and not able to find them, I found out that it is an 8080 assembler. (hey, it’s been a long time since… Read the rest

Retro Z80 computer (10) – Pi-Terminal

Posted on2022-01-262022-01-26

I got one of my raspberry Pi’s out of storage and made it to be a terminal for the Z80:… Read the rest

Retro Z80 computer (9) – BLINKENLIGHTS

Posted on2022-01-212022-01-21

A small project today. I added ‘BLINKENLIGHTS’ to my Z80. This term stems from an old sign that used to hang in computer rooms: ACHTUNG!ALLES TURISTEN UND NONTEKNISCHEN LOOKENSPEEPERS!DAS KOMPUTERMASCHINE IST NICHT FÜR DER GEFINGERPOKEN UND MITTENGRABEN! ODERWISE IST EASY TO SCHNAPPEN DER SPRINGENWERK, BLOWENFUSEN UND POPPENCORKEN MIT SPITZENSPARKEN.IST NICHT… Read the rest

Retro Z80 computer (8) – IDE disk

Posted on2022-01-162022-01-19

Where I originally thought that I could connect a floppy to my IDE card (silly me) I seem to have forgotten that IDE is a Hard Disk connection… Oh well, my brother still had an old Hard Disk laying around that he was prepared to part with. Got it today… Read the rest

Retro Z80 computer (7) – Almost complete

Posted on2021-12-212021-12-22

Here’s a picture of the progress so far. It now also includes a RTC (Real Time Clock) module. What you might also notice is the flat cable I attached between the serial card and the serial to USB connector. That connector, as you can see in previous posts, was attached… Read the rest

Retro Z80 computer (6) – It works!

Posted on2021-12-16

I am one happy maker, I got my Z80 computer working right after building. All went well! The first lines of output are the boot screen: CP/M And of course I wanted to see CP/M running: Z80 Basic And after that, on to Z80 Basic version4.7b:… Read the rest

Retro Z80 computer (5) – Dual Clock Module

Posted on2021-12-162021-12-16

Without an internal clock nothing happens inside a computer. It’s the clock that makes the computer ‘tick’, chew away instructions that is. Last I assembled this module; it contains two clocks. Both clock signals are being put on the bus on the Backplane board. It’s starting to look like something…… Read the rest

Retro Z80 computer (4) – Dual Serial Module

Posted on2021-12-15

And another one bites the dust… The Dual Serial SIO/2 module has been assembled and soldered. With this one I had to search for the value of the resistors, because the info was not in the documentation. Eventually I ended up looking at the pictures of an assembled one online… Read the rest

Retro Z80 computer (3) – Memory module

Posted on2021-12-152021-12-15

And the memory module for my Z80 computer is finished. It contains 512K of ROM and 512K of RAM memory.… Read the rest

Retro Z80 computer (2) – backplane and CPU board

Posted on2021-12-152021-12-15

Yesterday evening I assembled and soldered the backplane board and the CPU board. Around 600 solder joints…… Read the rest

Retro Z80 computer (1) – plans

Posted on2021-12-112021-12-15

This holiday season I’m going retro, and build my own Z80 computer from a kit. The kit offers all the separate parts and one has to assemble the whole thing… All the parts Modular design The design of this computer is totally modular. Because it has been thought out very… Read the rest

HAM-gadget (5) – menu structure

Posted on2021-11-072021-11-08

This weekend I built in a menu structure into the HAM-gadget. Also I created a possibility to store and retrieve settings to the ATMEGA328P’s EEPROM, so they are saved for the next time you switch on the device. For now, you have to retrieve them manually, but that’s quicker then… Read the rest

HAM-gadget (4) – keyboard added

Posted on2021-11-052021-11-06

After a lot of fiddling, trial and errors, I finally got the matrix keyboard to work. Also, as the project has passed the prototype stage, I threw together everything on a PCB in preparation for mounting it in a casing. Note to self:next time first cut the PCB to size… Read the rest

HAM-gadget (3) – connected the GPS

Posted on2021-10-242021-10-24

Finally got it to work After much fiddling and trying out different libraries I finally had a bright moment and reverted back to the library that has been specifically made for this GPS module by Velleman… Duh… prototype, software version 0.5 That worked, also after some tweaking of the wires… Read the rest

HAM-gadget (2) – new Arduino board

Posted on2021-10-232021-10-23

Arduino board left and center, GPS module on the right, GPS antenna on top Today some new stuff arrived. First of all the new Arduino RP2040 Connect board, a Wifi capable board with a much smaller form factor then the Uno clone I had before. Second came in the GPS… Read the rest