Last night I build 2 new boot selectors that is smaller than the last one.
This one only needs to chip sockets, some wires and a switch.
Look at my ‘Boot selector a500 version 2’ page for more info.
The VIC-20 specs:
CPU MOS 6502 at 1 Mhz (1.108404 Mhz for PAL and 1.02 Mhz for NTSC)
20Kb ROM and 5Kb RAM (expandable to 32Kb)
I’m not sure what I’m going to do with it yet, it’s in working condition but I’m thinking about adding Jiffydos and a internal 32Kb ram.
Today I’m happy.
With the mail my new Amiga 500 + arrived.
This will be my second Amiga I own.
I Started it up and the kickstart 2.0 boot image appeared on the screen.
The first tries to boot a floppy failed, but after some tries it started to work (Got a little rusty ?)
Quick inspection of the battery showed some corrosion, so I need to take some action.
So with some care and love she will be fine again, and be my best Amiga so far.
When trying out my new Gotek drive, My Amiga did her own thing.
When the Selector.ADF was loaded, the selection bar keep on scrolling down.
Checking the joystick circuit, I noticed another resistance between pin2 of joystick port 2 than the other pins.
First I checked the Resistor pack RP401 but it seems ok.
Then I replaced U15, a 74LS157 (multiplexer) this fixed the problem.
My Amiga is now running again.
Yesterday I was busy building a bootselector with a 74ls241, when ready I checked for short circuits, everything looks good.
But when powering the Amiga some smoke appeared from her…
I double checked the circuit, but couldn’t find any error..
I removed the 74ls241 from the schematics and used a 4 wire cable to connect the switch.
I wanted to use the 74ls241 to avoid having big cables running through her.
I tested the bootselector and it worked.
Couple of days back I received the Gotek floppy drive emulator from Ebay (only $18.10 ).
I want to use this drive with my Amiga, but before it can be used, I need to change the firmware so it will accept ADF images and support 880Kb (pc dual density drives only reads 720Kb)
I will create a story on how to do this.
To upgrade my Amiga 500 (rev 5.) to 1 Mb chip ram I need an A501 extension board or 16 ram chips.
As I can’t find an extension board, I started to look for 16 4256 or 41256 fast mode dram chips.
on Ebay I can find them for $2.50 per piece (so totaling $40.00 without shipping), this is to expensive for me, so I continued my search.
I found some shops that still sell them, but most are in the same price range (or charge high shipping costs for shipping to Europe).
But I seems to find one place now, but I’m not sure if this are the correct ones.
I send them a mail, asking for the brand, so I can check the datasheets
Check the Futurlec website, the part number seems correct, and for $0.95 per piece.