Search found 42 matches

by S_U_C
Mon Sep 20, 2021 11:51 am
Forum: Hardware
Topic: MZ-80K displaying garbage chars on screen
Replies: 5
Views: 53

Re: MZ-80K displaying garbage chars on screen

Hi, this is the stardard cpu not running screen display as the Z80 clears the screen using code. As you said, same result if no cpu fitted. First try a manual reset, a quick short on pin 26 Z80 to ground (0V) as the reset circuit may have failed. If you have a logic probe check to see if there is a ...
by S_U_C
Fri Aug 27, 2021 5:37 pm
Forum: Hardware
Topic: MZ-80K where to start to repair
Replies: 17
Views: 382

Re: MZ-80K where to start to repair

The video is a self contained unit consisting of a video ram driven by an binary counter the ouput of the video ram + binary counter drives the CG ROM, and output of thr CG ROM is serialised to produce the display. The 12 volts also powers the dynamic ram on the MZ80K so these could be cooked if sup...
by S_U_C
Tue Jul 27, 2021 9:02 am
Forum: Other
Topic: Text To Speech
Replies: 18
Views: 498

Re: Text To Speech

Hi, It crashes due to there is no code a $C000 for the USR() call, there are no data POKES to, or a LIMIT set to protect the $C000 area. From the listing “USR($C000,O$), I think the program refers to the JAMAR Speackeasy (the micro speech module) that plugs in to the printer/plotter connector. The c...
by S_U_C
Sun Jun 06, 2021 7:44 pm
Forum: Other
Topic: Machine Code program
Replies: 2
Views: 305

Re: Machine Code program

I believe this to be someone’s attempt at converting KNIGHT'S M/C VSN 3.1 and it contains bugs the obvious one is the paper out error which prints paper out but then is coded to print out part of the “no printer” error message half way though a word. Also the first 9 bytes have been corrupted with F...
by S_U_C
Wed Feb 17, 2021 11:26 pm
Forum: Hardware
Topic: MZ-80B project (Floppy Disk I/O Card cloning!)
Replies: 23
Views: 9870

Re: MZ-80B project (Floppy Disk I/O Card cloning!)

Hi I found a large A3 scan of the MZ-80A floppy disk card, this will work in the B if you dissable the CS/CE to the EPROM IC 3 PIN 8 to IC 5 PIN 1. add pull-up resister to IC 5 PIN 1
by S_U_C
Wed Feb 17, 2021 11:17 pm
Forum: Buy/sell
Topic: WTB: MZ80B FDD controller card
Replies: 5
Views: 1573

Re: WTB: MZ80B FDD controller card

I was correct there is one track that has to be cut to convert the A card to a B card the EPROM's CS/CE signal IC 3 PIN 8 to IC 5 PIN 1
IC 5 PIN 1 will need a pull-up resistor adding. see images
by S_U_C
Wed Feb 17, 2021 11:07 pm
Forum: Other
Topic: Original software from SUC for MZ 800
Replies: 4
Views: 866

Re: Original software from SUC for MZ 800

Hi the Sharp Users Club had died 1980-2020 due to lack of members, Last SUC magazine 2020 vol2 November issue is still at the printers (lockdown problems) I have a large selection of tape and disks for various Sharp machines. I have an 800 basic disk marked PIXEL (EPSON) but can not access it, as al...
by S_U_C
Wed Feb 10, 2021 5:53 pm
Forum: Buy/sell
Topic: WTB: MZ80B FDD controller card
Replies: 5
Views: 1573

Re: WTB: MZ80B FDD controller card

Do you want to run CP\M or do you want to extract data from the disks? I have a KroFlux and can read the disks except the boot sector, but I know what it is anyway. And I have my own software that can mount the KroFlux file and display directories and extract files. The Mz-80A FD card will work in t...
by S_U_C
Thu Sep 10, 2020 9:20 am
Forum: Hardware
Topic: Mz80-A no cursor
Replies: 8
Views: 3409

Re: Mz80-A no cursor

I had a similar fault on a MZ80K. I was the flash timer is not working. The K used a 555 timer and the MZ80A uses a 556 (IC51)+ caps C39,C40 On the A the start up order is the setup clear screen print ** MONITOR SA-1510 ** test for he USER ROM/RAM at $E800 (IC43 next to the Monitor ROM) print Newlin...
by S_U_C
Wed Jul 15, 2020 2:45 pm
Forum: Demoscene
Topic: MZ-700 demos
Replies: 80
Views: 45043

Re: MZ-700 demos

Note: just to make things more interesting The MZ-80K and MZ80A ROM and RAM opcode timings are the same. But the MZ700 runs opcodes faster in RAM than ROM as the LSI chip controls the /WAIT ine of the CPU and it adds 1 extra T-cycle to the opcodes in ROM. This speeds up the tape read/write routines ...