Search found 62 matches

by psmart
Thu Oct 08, 2020 7:43 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

How it sits within the machine. It plugs into the Z80 socket and into the Modulator Connector. You can connect the modulator to the original motherboard output or to the new graphics generator. There are 4 bits + 1 per colour, the 5th bit is needed to drive composite (requires > 2.0V whereas RGB is ...
by psmart
Thu Oct 08, 2020 7:40 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

Installed in the MZ700
by psmart
Thu Oct 08, 2020 7:39 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

Photos of the board.
by psmart
Thu Oct 08, 2020 7:32 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

I was waiting for you to terminate your project before asking if there is a way to get one, so I would certainly not refuse your offer :). Just a quick update, I've been in Austria for the last few weeks so I haven't completed everything yet, but the pictures will give you an idea. All functionalit...
by psmart
Tue Sep 08, 2020 11:53 am
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

One of the advantages using the FPGA is you build the frames and can manipulate them, harder to do in physical hardware as your encountering. In the FPGA I have a frame-buffer which I render during the blanking periods (H/V) at 120MHz, either 320x200x3 or 640x200x3, the number of frames per second d...
by psmart
Mon Sep 07, 2020 1:25 am
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

Hi Hlide, Very interesting read, thank-you I will have to consider how to do it as the BRAM is limited in the FPGA I chose. As you mentioned, a palette register could be employed, and if enabled, flip the actual colour bits on each frame with a 50% or even a programmable duty cycle (ie. red 50%, blu...
by psmart
Sun Sep 06, 2020 5:12 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

arnuphis wrote: Tue Aug 11, 2020 4:45 pm Thanks! I ordered a bag of cassette player belts of various sizes. So hopeful that one of them is the right length!
I forgot to look at my MZ80B, sorry about that, got carried away with my projects!!! Did you ever get the MZ80B tape drive to work?
by psmart
Sun Sep 06, 2020 5:11 pm
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

Welcome as well. It is probably easier just to write your own video hardware in VHDL, that way programming it can be as hard or as easy as you deem fit :) - ie. The board Im making below, recreates the MZ700 (/80A/80B) video hardware in the FPGA along with 640x200 pixel graphics 8 colour (due to lac...
by psmart
Sun Sep 06, 2020 5:07 pm
Forum: Hardware
Topic: Mz80-A no cursor
Replies: 8
Views: 2214

Re: Mz80-A no cursor

No cursor normally means the initialisation hasn't completed, either because it made a jump to User ROM, Floppy ROM or the DRAM is corrupt. Check to see if there is a User ROM installed (ROM or RAM), remove it if so. If there is a Floppy interface connected then unplug that (this is normally only av...
by psmart
Tue Aug 11, 2020 9:35 am
Forum: Off-topic
Topic: Introduction
Replies: 56
Views: 24629

Re: Introduction

I will have to check later, I stripped it down completely about a a year ago but too long ago to remember!!! One of the things I keep planning to do, but never get around to it, buy belts for all the machines I have, all are still on original!! My MZ80A is fine reading and writing tapes it makes but...