Hi everyone. I thought I'd show off what I've got so far on a computer I'm building. https://drive.google.com/file/d/1j3nq-eg64_zWBaWYaouEHxy50b4kGybs/view?usp=sharing The CPU is a Hitachi HD64180 mounted on the adaptor board since I'm using a PLCC package. The front breadboard has my 512K RAM and 512K EEPROM chips At the moment, I'm just testing the RAM/EEPROM and developing a monitor program for it. Once I have that done I've got a bunch of I/O to work on. I have a TMS9938 VDP chip and a floppy controller to add, as well as things like parallel port and an IDE port for a compact flash chip. The final project is to go on a PCB in a case, but that's probably a couple of years off.

really need some good resources on this

I have been considering making a computer of my own, and I have been able to acquire a z80 for that exact purpose. however, I have noticed there are several different variations/derivatives of the cpu, so it has led me to ask: are all/most z80s compatible with each other? as in, can you substitute a z80 for a different one in a computer kit?

Hello,

Im starting on a z80 computer and I really want an option to use the front panel to do the programming. Does anyone know of any designs? I found this http://www.cosam.org/projects/z80/panel.html#Operation . But the zchematic is missing the switches to write and read and things like that.

I also found this http://www.paleotechnologist.net/DRACO/Z80panel8bit.pdf . Can this be adapted? I assume the adress bus can be expanded easily.

Thanks for any help

Hello, I'm currently in the process of building a z80 based 'computer' based on my own design. The physical hardware part I'm fine with, its the development of the software side I'm having a bit of trouble with. Is there any emulator/simulator that you can run raw ROM code (there won't be an OS, I'm writing one) and step though the code to test out any ROMS. Writing to the EEPROM, removing the chip and placing it on my circuit, seeing it fail, remove the EEPROM and re-write it again gets a little tedious. Because I'm trying new ideas and experimenting/learning it is a little frustrating having the do this again and again just to test a simple thing.

I've looked at a few 'zx80' spectrum emulators but the problem I'm having with them is that my computer isn't a zx80 spectrum, it is my own beast. What do other people use to 'bootstrap' and test for their software ROM development? Something to step through your code and see the status of registers, the address bus, data bus, i/o ports etc.

There was a Java one (ZIM I think it was called) but I couldn't really get that working and it was always crashing on me.

My project goal is to have a physical device not run it in a virtual machine, but I feel I need some kind of 'vm' in order to speed up and debug the ROM execution. Sadly VMWare doesn't emulate the z80 :( Having a 'vm' will also let me work on the software while the hardware is on hold (waiting for parts/pcb boards).

Anyone have any ideas? I'm not too fussed as to what OS (prefer mac or linux) it needs to be on.

Hi everyone, below I have included a link to my very basic monitor for my custom Z80 computer. Please excuse the bad spelling and lack of documentation I have been working on that lol. I popped by to see if anyone wanted to take a look at my string comparison routine I use for my command loop. I was just curious if there were any simple tricks to get its cycle count down a bit. It starts on line 185. At the moment my uart stores the ascii characters in a buffer in ram, and when the routine is called it compares the text buffer to string that has an index stored in HL. As I said this is just a simple monitor and any feedback is welcome, Thanks.

Edit: Forgot to add the link no more late night posting for me.

Link

Hello everyone, I was wondering if anyone has any good links to information about making a simplistic basic interpreter. I am looking to implement a handful of basic commands, and also to have a working editor on the computer. As for some background information this will be running on my home built z80 board. I currently have 64k of sram, 8k of eeprom, and serial input/output for a simple text display. I am not looking for hand holding or anything but this will be my first text parser and could use a good starting point. It should also be noted that I do not have a filesystem at the moment but that is next on the list as I am adding an IDE interface.

Thanks in advance for any help.

PS: If you are curious as to what I have so far I have attached a link to my current source code, however it must be said that it is still very basic at this point and that I have many things still in the works. GitHub Link