Electronics hobby blog

A while back I have bought a cheap second hand Commodore 64. Unfortunately it was broken, next to the PLA chip which I have fixed by binding a custom CPLD version of it, the BASIC ROM chip (901226-01) was also broken.

The most important chip in commodore 64 computer is the PLA chip. When this chip is broken, nothing will work and most certainly you will get a black screen after you try to turn it on.

FPGA's and CPLD's are certainly very cool devices. It is possible to create you own logical circuits and emulate real hardware chips on the lowest level. For this test project we will use Alera CPLD which is also known as MAX3000A and it's full code is ALTERA  EPM3064ATC44-10.

I have decided to start a new project and that is to build an arcade cabinet. The first parts needed for the project were delivered, so I wanted to write something about them.

Recently I have bought an Apple Macintosh Plus. Everything was working except one key on the keyboard. The previous owner just glued it permanently to disguise the damage. The key in question is the "Clear" key. It is not used very frequently, that is of course if you are not a heavy user of the Calculator Application. Nevertheless I wanted a fully functional keyboard, so I decided it to fix it.

The MSX2 NMS 8250 that I have, cames with a PHILIPS VW-0030 printer. It is easy to print documents using the MSX2 Home Office 2.0 application, but I wanted to be able to print from a Windows PC.

To create single sided disks on a PC (Windows XP) we will need a floppy drive that is connected to the FDD controller. The tests that I have done with USB floppy drive failed. It simply did not want to recognise single sided (360K) formatted floppy disks.

MSX2 Philips NMS 8250 computer has a build-in double density (DD) floppy drive. There a various sites on the internet where you can download floppy disk images. For example on planetemu website you can browse MSX2 various disks section and "télécharger", as the site is in french language, and means "download".