Search found 7 matches

by ralle
Sun Dec 12, 2021 7:45 am
Forum: Hardware hacks and extensions
Topic: Parallel port MIDI interface
Replies: 26
Views: 9088

Re: Parallel port MIDI interface

Oh dear, something for hardcore hobbyists who won't stop at anything. But it works.
by ralle
Fri Dec 03, 2021 6:18 pm
Forum: Hardware hacks and extensions
Topic: ROM RAM Extentions
Replies: 7
Views: 3602

Re: ROM RAM Extentions

A forum colleague from robotics technology brought me a couple of EPROM files in the format usable for the KC. For this I have an EPROM burner. The handicrafts will only be in January.
by ralle
Fri Dec 03, 2021 6:15 pm
Forum: Hardware hacks and extensions
Topic: Parallel port MIDI interface
Replies: 26
Views: 9088

Re: Parallel port MIDI interface

Something like this was built in the GDR era. In German, however.
http://robotron.webhop.net/files/kc/MIDI-rfe11_88.pdf

With the 1.77 MHz of the KC there were timing problems, so you can use another method, state-oriented programming. For the C64, i.e. 6502 CPU, the SIO 6850 was used.
by ralle
Mon Nov 22, 2021 8:51 pm
Forum: Hardware hacks and extensions
Topic: ROM RAM Extentions
Replies: 7
Views: 3602

Re: ROM RAM Extentions

Dbug wrote: Sun Nov 21, 2021 8:35 pm
ralle wrote: Sun Nov 21, 2021 8:16 pmBut what is meant on page 3 is still a mystery to me.
Page 3 is the 256 bytes area from $300 to $3FF where all the I/O registers (VIA, Floppy Disk Controller, ...) are mapped.
https://wiki.defence-force.org/doku.php ... page_3_i_o
thanks...
by ralle
Mon Nov 22, 2021 8:49 pm
Forum: Hardware hacks and extensions
Topic: ROM RAM Extentions
Replies: 7
Views: 3602

Re: ROM RAM Extentions

I could try that. The first drawing addresses the 16K EPROM from C000h, as I can see. And therefore far easier than that of the Z1013. The problem with the Z1013 is that there is a 1K image memory in the 16K block from EC00h to F000h. That's why I had to castrate the 2nd 2716 in half during the repl...
by ralle
Sun Nov 21, 2021 8:16 pm
Forum: Hardware hacks and extensions
Topic: ROM RAM Extentions
Replies: 7
Views: 3602

Re: ROM RAM Extentions

First I had to think about what was meant by D-toggle, i.e. a flip-flop. But what is meant on page 3 is still a mystery to me. The presented plan can be used as an aid to find a solution. Well, the 6502 is a bit different than the Z 80. Although I usually have a clone of the Z80. The 74138 is actual...
by ralle
Sun Nov 21, 2021 8:59 am
Forum: Hardware hacks and extensions
Topic: ROM RAM Extentions
Replies: 7
Views: 3602

ROM RAM Extentions

Hi there, I would like to connect external ROM and RAM (static) to an Oric-1 16K. The lines / MAP and O1 (O2) are used for this purpose. How do I have to understand these lines? An external ROM idea would be the Diagnostic ROM and possibly the EXBASIC 1.1. Since the structure is similar to that of t...