Hardware on csegura

Fixing Sharp MZ-700

Fri, 23 Aug 2024 00:00:00 +0000

Fixing Sharp MZ-700

Time to fix the Sharp MZ-700, I have this computer for a while, and it was not working. I decided to fix it. I opened the computer and I found that the power supply was not working correctly. I decided to do the standard procedure, replaced suspects capacitors and voltage regulators. Here are some pictures of the process:

This machine was manufactured in 1982, and it was a very popular computer in Japan. It was used in schools and homes. It has a Z80 CPU, 16KB of RAM, and 16KB of ROM. It has a built-in tape recorder, and it can display 40x24 characters in 8 colors.

ISA-PicoMem

Wed, 05 Jun 2024 00:00:00 +0000

I’m restoring this wonderful IBM XT 5150, machine powered up, but there wasn’t os. Floppy drive was`t working, I tried to boot from a 720k floppy disk, but it was impossible. So looking for a solution, I found a ISA-PicoMem (https://github.com/FreddyVRetro/ISA-PicoMEM/tree/main) card, a wonderful card that allows you to boot from a SD card, add memory, and is able to connect to a network using wifi and ne2000 drivers, of course you need install mTCP.

Connecting a Z80 to a Raspberry Pi

Mon, 18 Mar 2024 00:00:00 +0000

I have a long history with computers, starting with a Sinclair Zx81 that I still own, followed by other models and others that I wished for, as time went by.

A while back, I found an old box with some old processors, x386, x486, a few Pentiums first generation and two Zilog Z80. Then I got a kind of retro-feeling in my mind and I watched some YouTube videos about them. One of them was the classic nop-test, I had fun with this for a whole afternoon.

Fixing Dragon 32 Power supply

Sat, 16 Mar 2024 00:00:00 +0000

This morning the Dragon 32 power supply broke. I have a Dragon 32 that I bought one time ago. But when I tried to turn it on, it didn’t work. I checked the power circuit inside of the Dragon 32 and found that the regulator was broken.

It was a LM340T 7812, 12v regulator, so I replaced it with a new one. But when I tried to turn it on, it didn’t work.

IBM 5150 Motherboard

Sat, 03 Feb 2024 06:37:07 +0100

I have been repairing the IBM 5150 motherboard.

Tantalum Capacitors are known to fail, :-) This is the famous C56

Almost each memory chip had a tantalum capacitor.

Also ISA slots had tantalum capacitors.

This ones, near the power supply connector, were also tested.

IBM Model M keyboard

Sat, 03 Feb 2024 06:37:07 +0100

I have been repairing the model m keyboard, but not lucky this time. The membrane is broken and I have to replace it. I have to find a replacement membrane.

Fixing the Dragon 32

Sun, 14 Jan 2024 07:07:07 +0100

I have been repairing the Dragon 32

When I powered it up, the screen was all garbled. I opened it up and found a capacitor that was bulging.

Nude Dragon

Replaced Capacitor

First attempt to fix it was to replace the bulging capacitor. I replaced it with a new one, but after powering it up, the cursor was missing.

Finally I have had to replace most of the capacitors on the board.

LLM Conversation Commodore 64 vs ZX Spectrum

Wed, 11 Oct 2023 07:07:07 +0100

Playing with langchain this is the conversation between a Commodore 64 and a ZX Spectrum.

Debate rules

You are in a debate your goal is to persuade your conversation partner of your point of view. 
Argue about topic polite. Be concise and conclusive use arround 60 words.
DO look up information with your tool to refute your partner's claims.
DO NOT fabricate fake citations.
DO NOT cite any source that you did not look up.
Do not add anything else.
Stop speaking the moment you finish speaking from your perspective.
Context: {memory}

Conversation for 10 rounds