I have the same issue with an MZ-700, random characters on startup (in colour)
Could it be the RAM used for video perhaps?
Search found 8 matches
- Sun Oct 10, 2021 12:46 pm
- Forum: Hardware
- Topic: MZ-80K displaying garbage chars on screen
- Replies: 12
- Views: 5975
- Mon Apr 13, 2020 5:38 pm
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
Hi everyone. Just to update you, the display is absolutely identical everytime I switch on. I swapped the CPU for one I had spare which I believe is working but the output is just the same. It doesn't beep on startup which would support the theory it's not using the Monitor ROM program at all? Gorth...
- Sat Apr 04, 2020 7:07 am
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
I've also tried removing the Z80 processor and it's still the same. Does that suggest something more fundamental?
- Fri Apr 03, 2020 2:25 pm
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
I've also tried removing the processor and get exactly the same. Seems like something more fundamental perhaps?
- Thu Apr 02, 2020 11:18 am
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
Hi Pacman, you are correct. If I remove the ROM it's exactly the same.
- Wed Apr 01, 2020 12:33 pm
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
I haven't had chance to try anything out yet but in answer to Gortho's question there wasn't any response from the keyboard.
By the way, does the MZ700 beep on startup becuase this one doesn't - might be a clue if it's supposed to?
By the way, does the MZ700 beep on startup becuase this one doesn't - might be a clue if it's supposed to?
- Sun Mar 29, 2020 11:40 am
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
Re: MZ700 video problem
Hi Pacman, I'll give that a go and let you know how I get on.
- Sat Mar 28, 2020 7:48 am
- Forum: Hardware
- Topic: MZ700 video problem
- Replies: 25
- Views: 20003
MZ700 video problem
Hi All
First post on this great site!
I'm trying to resurrect an old MZ700. Have got the power supply working but the video output is scrambled - see photo.
Note that the picture is not entirely random, it's identical each time I switch the machine on.
I was thinking RAM maybe?
Any ideas?
Cheers
First post on this great site!
I'm trying to resurrect an old MZ700. Have got the power supply working but the video output is scrambled - see photo.
Note that the picture is not entirely random, it's identical each time I switch the machine on.
I was thinking RAM maybe?
Any ideas?
Cheers