personal history of personal computers

there is a sing rail that guide the head. At the back of the rail is a small nylon tab that holds it in place. The way they mad it, it is over stressed and will have failed. This means the rail is not held down securely. Eventually the rail will pop up, not being held down securely any more. You will find the first indication is that the disk will not eject properly. the temptation is to pull it out, thinking it is just a sticky eject, but that isn't the problem. It is catching on the head. Eventually it will catch really well and you'll rip the head of the mount. At this point the disk can not be repaired. It is an unusual drive, being single sided and requiring the DriveReady signal. It also has a build in cable instead of the standard edge connector and power connector. Most of the new drive no longer have the DriveReady signal, even as an option. One can make changes to the software if you know how to use the data or sector pulse as a DriveReady. This usually requires a one shot to hold the pulse for the software to recognize the pulse. There are several things on can do with it. With a few simple modifications, one can increase the RAM ( mostly just installing ) but for text you can't have more than 100K. It is possible to use a newer version of the software that includes the assembler. One of the more frustrating things is that it normally only has drivers for Cannon printers, with the excepting that it will also do the FX80 compatible printers. It is not too hard to write one's own printer drive and substitute it for one of the printer drivers. This is normally done such that it will use a portion of the disk and overlay in RAM for one of the drivers. I've done this to use a HP pcl5 type printer. ( I don't support all of the funny characters though ). You can write your code in the editor and compile it into RAM. As an extension, it can be saved on onto the disk such that it is available the next time you use that disk. As I recall, the official software is 1.73. The new code with the assembler is 2.40 ( never released ). I have a copy of that version. Anyway, the RAM can be expanded by putting chips into the sockets and adding socket to the last row. I've expanded the RAM even more by adding a large CMOS RAM to an unused address decoded area. One does have to make a minor hack and add a gate to deal with the high/low byte 68000. I just mount a IC dead bug but one does have to lift a couple leads of the 68000. I use the extra RAM to recompile the Forth and editor software, to blow as an EPROM. I can compile it to run in the RAM space or the EPROM area. This allows me to test it first before changing the constant for the offset. Dwight ________________________________ From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Cameron Kaiser via cctalk <cctalk at classiccmp.org> Sent: Monday, January 4, 2021 3:19 PM To: cctalk at classiccmp.org <cctalk at classiccmp.org> Subject: Re: personal history of personal computers I love the form factor of my Cat. Wish it was easier to "do things" with it though. Don't leave us in suspense! However, mine seems to be fine. -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com<http://www.floodgap.com> * ckaiser at floodgap.com -- Why is it you can only trust short, dumpy spies? -- Hogan, "Hogan's Heroes"