Tim Holyoake
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timholyoake.uk
Tim Holyoake
@timholyoake.uk
130 followers 240 following 270 posts
RetroComputing. Liberal Democrat. Caterham 7 Owner. In remission from Mantle Cell Lymphoma.

More often at https://oldbytes.space/@psychotimmy

Blogs at https://z80.timholyoake.uk/ , https://mcl.timholyoake.uk/ & https://railwaywalks.timholyoake.uk/
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timholyoake.uk
Ottery St Mary evening #Devon #DevonLife
November 5, 2025 at 9:38 PM
timholyoake.uk
Running the emulator at 200MHz is a definite improvement - it's only 2 seconds slower than the real thing for the primes up to 10,000.

#RetroComputing #Sharp #MZ700 #PicoMZ
Emulator output on the left - 8m 36s for the primes below 10,000. Real machine output on the right- 8m 34s for the same task.
November 2, 2025 at 5:10 PM
timholyoake.uk
Sunday afternoon benchmarking session. A real MZ-700 vs my emulator. The emulator is currently 20% or so too fast when running on a 220MHz Pi Pico. Should be easy enough to slow down!!

#RetroComputing #PicoMZ #Sharp #MZ700
The screen for the Pico MZ-700 is on the left, above the real MZ-700. The output for the real machine is on the right. They're both running endless prime number calculations using the same BASIC program. The emulator is currently too fast!
November 2, 2025 at 4:32 PM
timholyoake.uk
Yep 😊
The keyboard of a Sharp MZ-80K with its unique 25 blue graphics keys
November 1, 2025 at 9:48 PM
timholyoake.uk
I seem to be getting close to having a reasonable #M700 #emulator running. There are some oddities that I need to look into (e.g. keyboard handling for monitor in ROM seems different to monitor in RAM) and I need to retrieve my real MZ-700 to check various timings.

#RetroComputing
Pico MZ-700 emulator running my version of Moonlander. The spacecraft is just about to crash on Pluto and make a big crater. Pico MZ-700 emulator generating the prime numbers between 1 and 400 in 8 seconds. Allegedly.
November 1, 2025 at 5:18 PM
timholyoake.uk
Sorted out the display of the upper 256 characters today. Took longer to figure out than it should have ...

#RetroComputing #SharpMZ700 #Emulation
The upper 255 characters of the Sharp MZ700. Blue characters on a yellow background.
October 29, 2025 at 5:47 PM
timholyoake.uk
Looking forward to witnessing this madness for the first time!
Souvenir program for the Ottery St Mary tar barrels 2025. The cover shows a man engulfed in flames from carrying a lit tar barrel through the streets of the town.
October 22, 2025 at 1:15 PM
timholyoake.uk
Ottery St Mary morning
Silver Street, Ottery St Mary, Devon.
October 22, 2025 at 10:26 AM
timholyoake.uk
New from me: A Pico MZ-700 ?

z80.timholyoake.uk/a-pico-mz-700/

#RetroComputing #Sharp #MZ700
The Pico MZ emulator showing the boot screen. It is white text on a blue background and reads MONITOR 1Z-013A, followed by a flashing block cursor
October 21, 2025 at 4:25 PM
timholyoake.uk
It's a start! Hacked the monitor into my mz80k/a code and it runs up. Now comes the painstaking stuff - keyboard mappings, colour, clock accuracy etc etc etc ... #RetroComputing #Sharp #MZ700
Sharp MZ700 monitor announces itself for the first time on my Pico mz platform. Colours are wrong, as is everything else, but it's a start.
October 19, 2025 at 2:52 PM
timholyoake.uk
Here we go again ...

#RetroComputing #Emulation #Sharp #MZ700
A screenshot showing the github picomz-80k repository with a newly created branch called mz-700-emulation - an autumn / winter project!
October 18, 2025 at 2:00 PM
timholyoake.uk
Doggy ate a spatula
A broken wooden spatula, caused by an over enthusiastic doggy desperate to read the latest Lib Dem literature. You can just see a tooth mark around an inch from the top.
October 12, 2025 at 12:10 PM
timholyoake.uk
Sidmouth morning
Seven sleepy donkeys at the Sidmouth donkey sanctuary.
September 28, 2025 at 10:34 AM
timholyoake.uk
Ottery St Mary afternoon
Ottery St Mary Silver Band playing "Una Paloma Blanca" or "I am a cider drinker". Take your pick!
September 27, 2025 at 1:27 PM
timholyoake.uk
Weasels King Henry morning
A field of cows in Ottery St Mary
September 25, 2025 at 12:31 PM
timholyoake.uk
Ottery afternoon
The tumbling weir, Ottery St Mary
September 22, 2025 at 2:53 PM
timholyoake.uk
For comparison:
My Sharp MZ-80K. Yellow keys on the bottom row, dark blue graphics keys.
September 21, 2025 at 6:08 PM
timholyoake.uk
A photo from yesterday, of the MZ-80K at the National Museum of Computing @tnmoc.bsky.social. The cursor keys are green. On mine (and every other MZ-80K I've seen) they're yellow. I wonder why this one is so odd? The blue keys are also closer to turquoise. Left in the sunlight too long? #Sharptember
Sharp MZ-80K with green cursor / space bar / carriage return keys.
September 21, 2025 at 6:02 PM
timholyoake.uk
Damn. I'm going to have to dig out the 1985 source code of my unfinished Pegasus emulator and finish it. #RetroComputing
The Pegasus display at the national museum of computing. There's a picture of the Pegasus when it was running at the science museum, a card noting that neither of the surviving examples are operational, 3 boards from a Pegasus and the book of the history of the machine.
September 21, 2025 at 4:13 PM
timholyoake.uk
Ottery afternoon
Cadhay House
September 12, 2025 at 1:18 PM
timholyoake.uk
Ottery afternoon
Old Town Hall, Ottery St Mary. Now the heritage museum.
September 9, 2025 at 1:39 PM
timholyoake.uk
The early Sharp MZ series machines were "clean". Unlike most other 1980s micros you loaded the programming language you wanted to use from tape or disk into RAM. This gave great flexibility, but about a 3 minute wait on a tape based MZ-80K before you could write 10 PRINT "Hello Word!" #Sharptember
Four Sharp MZ-80K language manuals. Express BASIC, SP-5025 BASIC, Z80 Machine Language and Sharp Pascal.
September 3, 2025 at 9:30 AM
timholyoake.uk
I found this in my files. You'll have to imagine the CAD program in the middle of the window, but it neatly shows/describes the aspects of the window manager we used. This is from the GENIX 2.0 port, but I'm pretty sure nothing changed in the 42nix version. (My handwriting was legible in 1985!)
A page from a notebook explaining how DOGS ran in a window on the Whitechapel MG-1 workstation.
September 2, 2025 at 9:02 AM
timholyoake.uk
If you don't have room for a real Sharp MZ-80K or MZ-80A, there's always my Raspberry Pico based emulator for both of these machines! Here it is running in 80K mode playing Sharp's Space Invader program. #Sharptember

z80.timholyoake.uk/the-pico-mz-...
The Pico MZ-80K running on an RC2014 VGA card. The screen shows the Sharp Space Invader game in progress.
September 1, 2025 at 5:29 PM
timholyoake.uk
Ottery St. Mary afternoon
Samuel Taylor Coleridge statue, Ottery Church. Ottery St. Mary Church and grounds
August 21, 2025 at 4:13 PM