A little update

Last couple of months I’m very busy with all kinds of little projects.

Some of the JoySwap boards that are ready
ZX81 with broken ULA

I’m looking through my stuff, collected over the last 20 years, My son is getting older and needs more space so I need to move my computers and other equipment to another room.

I also received a broken ZX81 (dead ULA and broken keyboard membrane), I already got another main board to check if it has a working ULA.

Another thing I received is a broken 1551, I think the TIA (6525) in the drive is broken, as this chip is rare, I need to find another way to replace it (CPLD ?).

I created about 15 pieces of the JoySwap to be sold, but currently I’m still writing a little installation manual.

I ordered some PI1541 boards and currently I’m waiting for the parts, the PI1541 looks very promising.

New provider

I’m moving the website to a new provider.
This could cause some downtime while moving the site.

The reason behind the move is the bad service my current provider (mijndomein.nl) gives.
After migrating/updating their hosting servers last month (22 june 2018), all links on my site were broken.
It took 5 days to get response from their support.
The responses clearly shows they don’t read the questions/requests.

264 joystick converter

last couple of months, I was very busy creating several new interfaces and converters.
one of these is the joystick converter for the 264 family systems.
this family has a 8 pin mini din as joystick connection.
a simple converter with only wires should work for a default joystick.
But joysticks that uses 5 volt for something like autofire would fail.

normally a joystick uses a switch between ground and a direction pin.
the 264 family uses a “select line” instead.

the converter I found on the internet used a latch (74f244) to control when the signals are send to the computer.
this way “more advanced” joysticks can be used.

for build details follow this link.

other things I’m building are a joystick switch to be build into the c64 and a diag264 harness.

SD2IEC build

Added the Card Detect signal that was missing on the header

Last week I managed to complete my SD2IEC.
The PCB I created contained some little faults.
The silkscreen of the LEDs was wrongly positioned, and the DATA and CLOCK label of the serial port were swapped.
So I fixed the issues by swapping back the labels, and selecting a correct package for the LEDs (fault was in the component library).
The fixed version can be found on easyeda.com
I tried to program the AVR with AVRdude, but only got an error back (some sync error).
So finally I took my old STK500 development board, and downloaded AVRStudio from Microchip.
With this I could program the MCU and after hooking up the SD2IEC to my C64, I could access it like a drive.
(I uploaded the SW1 bootloader for the M1284P with the following High:0x92, Low:0xEF and Extended:0xFD)
On the 2nd photo you see a modification of the mico SD module.
the module didn’t have the card detect signal on it’s pins, so I wired a wire for this signal.
the card detect can also be controlled by the dip switches.
another signal that is not pressent is the write protect signal.
Micro SD cards don’t have this, so this is also handled by the dip switch.

HCC meeting 17 February 2017

last Saturday 17 February it was again the 2 monthly meeting of the Commodore HCC club.
on these meetings not only Commodore fans are comming, but also other retro computer fans join.
You will find MSX, Atari and other systems here.
I had a “little” gift to the guy that is starting a computer museum, a Toshiba hard disk from 1980.
I have no clue what capacity it had, but guessing it will be around 5 to 10 MB.
The little 2.5″ pata hd on top is from Jan Derogee (the creator of the Cassiopei and 1541-III). he was sitting in opposite of me.
My collection also grew a little with a oceanic drive, c64 test set, some books and DD floppies and an Amiga 500.
The Amiga has a broken drive and the case is not very nice, but I will use the keyboard to fix my Amiga 500+.
The main board will be stored for spare parts, or for testing purpose.

Visit the Facebook page of the Commodore HCC club to learn more about the meetings

Finally an update on the kernal selector for the Commodore 16

I finally managed to create a page on the kernal selector for the Commodore 16.
Last couple of months I was very busy repairing an Amiga 2000.
But last week I made some time to create a schematic of the circuit I created.
The circuit uses an Arduino Nano to listen to the reset line and reacts to it’s use.
this way you don’t need to drill a hole in the case, and the already existing reset button can be used to control multiple mods.