Simon Harris
@simondo65.bsky.social
Software engineer at @imperialcollegeldn.bsky.social, doing research in orthopaedics.
Loves model trains, science fiction and vintage microprocessors, doesn't own an anorak. Also likes to cook and take photographs, not necessarily of my cooking.
Loves model trains, science fiction and vintage microprocessors, doesn't own an anorak. Also likes to cook and take photographs, not necessarily of my cooking.
for a Z80, if you can make HL point to a byte of scratchpad I think you can use RLD. If I understand it right, if you start with your 4 bit number in A, you’d do
LD (HL),A
RLD
LD A,(HL)
LD (HL),A
RLD
LD A,(HL)
November 1, 2025 at 5:11 PM
for a Z80, if you can make HL point to a byte of scratchpad I think you can use RLD. If I understand it right, if you start with your 4 bit number in A, you’d do
LD (HL),A
RLD
LD A,(HL)
LD (HL),A
RLD
LD A,(HL)
Note to self: don’t cock it up tomorrow!
November 1, 2025 at 12:17 AM
Note to self: don’t cock it up tomorrow!
Nor in my local shopping centre.
No shopping allowed for ICE in England!
No shopping allowed for ICE in England!
October 1, 2025 at 5:27 PM
Nor in my local shopping centre.
No shopping allowed for ICE in England!
No shopping allowed for ICE in England!
This was happening 10 years ago when I was in Vienna. Why can’t we be more like Vienn?
September 13, 2025 at 11:14 PM
This was happening 10 years ago when I was in Vienna. Why can’t we be more like Vienn?
A bit flummoxed by the timing and the London skyline, so didn’t get to see it in its full blood-moon totality, but at least we got to see some of it.
September 7, 2025 at 8:02 PM
A bit flummoxed by the timing and the London skyline, so didn’t get to see it in its full blood-moon totality, but at least we got to see some of it.
They can lip-read, you know!
September 5, 2025 at 12:34 PM
They can lip-read, you know!
That reminds me, need to buy more Port.
August 21, 2025 at 1:48 PM
That reminds me, need to buy more Port.
Sign I saw waiting for my hospital appointment this afternoon. I didn’t check the medical credentials of the pigeons.
August 12, 2025 at 8:08 PM
Sign I saw waiting for my hospital appointment this afternoon. I didn’t check the medical credentials of the pigeons.
On the workbench at the moment. A brass kit for a Midland Railway D418 milk van in 4mm scale EM gauge. The kit is from 51L.
July 29, 2025 at 11:16 PM
On the workbench at the moment. A brass kit for a Midland Railway D418 milk van in 4mm scale EM gauge. The kit is from 51L.
… and these are the photos and drawings it was based on.
July 20, 2025 at 3:58 PM
… and these are the photos and drawings it was based on.
Thanks - yes, it started out as a sheet of art mounting card. Even the window frames were scratch built from brass sheet and wire!
The brickwork was embossed card overlaid onto the structure.
This is how it all started!
The brickwork was embossed card overlaid onto the structure.
This is how it all started!
July 20, 2025 at 3:56 PM
Thanks - yes, it started out as a sheet of art mounting card. Even the window frames were scratch built from brass sheet and wire!
The brickwork was embossed card overlaid onto the structure.
This is how it all started!
The brickwork was embossed card overlaid onto the structure.
This is how it all started!
The wagon on the left is from a Slater’s kit. The one on the right breaks my ‘everything is something I made’ philosophy - it’s a Wrenn wagon I had since I was a child. Allowed for obvious reasons!
July 20, 2025 at 11:07 AM
The wagon on the left is from a Slater’s kit. The one on the right breaks my ‘everything is something I made’ philosophy - it’s a Wrenn wagon I had since I was a child. Allowed for obvious reasons!
Here’s a lockdown project - a mill that used to exist near Blunham, Bedfordshire, built based on Victorian sketches, a couple of blurry photos and some imagination.
July 20, 2025 at 11:04 AM
Here’s a lockdown project - a mill that used to exist near Blunham, Bedfordshire, built based on Victorian sketches, a couple of blurry photos and some imagination.
You may want to give them a good clean.
July 10, 2025 at 10:43 AM
You may want to give them a good clean.
Screenshot from today's guardian.
Left: Gaza, Right: Kyiv. Basically the same picture yet we only have an arms embargo against Russia.
Left: Gaza, Right: Kyiv. Basically the same picture yet we only have an arms embargo against Russia.
July 4, 2025 at 9:56 AM
Screenshot from today's guardian.
Left: Gaza, Right: Kyiv. Basically the same picture yet we only have an arms embargo against Russia.
Left: Gaza, Right: Kyiv. Basically the same picture yet we only have an arms embargo against Russia.
Would that be this Byline Festival?
June 18, 2025 at 5:59 PM
Would that be this Byline Festival?
Mix this with lemonade and you’ve got yourself a glass of Hand shandy.
May 19, 2025 at 8:07 PM
Mix this with lemonade and you’ve got yourself a glass of Hand shandy.
And some background information from the press release about Sinclair Research.
May 13, 2025 at 2:50 PM
And some background information from the press release about Sinclair Research.
Three more pages from the press release giving some technical information on the ZX80...
May 13, 2025 at 2:49 PM
Three more pages from the press release giving some technical information on the ZX80...
Here are a few pages from the press pack...
May 13, 2025 at 1:41 PM
Here are a few pages from the press pack...
Is there a more lovely tree than a horse chestnut full of candle blossom?
May 10, 2025 at 4:56 PM
Is there a more lovely tree than a horse chestnut full of candle blossom?