Search found 290 matches

by Silicebit.
Tue Jun 08, 2021 6:06 pm
Forum: Hardware hacks and extensions
Topic: TEAC FD-55GFR - best 5.25" floppy for retro hacking
Replies: 2
Views: 247

Re: TEAC FD-55GFR - best 5.25" floppy for retro hacking

I like the TEAC disk drives!




The 5.25" disk drive is a TEAC FD-55BV-34-U, and the 3.5" disk drive is a TEAC FD-235HF. Both works great!
by Silicebit.
Tue May 04, 2021 9:25 pm
Forum: Hardware hacks and extensions
Topic: Oric V23 Modem
Replies: 56
Views: 5782

Re: Oric V23 Modem

Ok, here is the schematic. Oric_serial.jpg This interface is a serial TTL interface, not RS232 compliant. You need a MAX232 IC to translate TTL levels to RS232 bipolar levels and viceversa. Please see TIA/EIA-232-F standard https://cw.fel.cvut.cz/b191/_media/courses/be2m37mam/tasks/mam-busses.pdf An...
by Silicebit.
Tue May 04, 2021 7:34 pm
Forum: Hardware hacks and extensions
Topic: Oric V23 Modem
Replies: 56
Views: 5782

Re: Oric V23 Modem

Hi Mike! I think you don’t have a real RS232 interface. Please, could you take a pic of inside of interface?
by Silicebit.
Sat Jun 20, 2020 6:20 pm
Forum: Hardware hacks and extensions
Topic: Erebus.
Replies: 6
Views: 1815

Re: Erebus.

... As noted in another posting, this sort of thing needs to be done on any other thing on the IO control line though (because a.n.other device may drive the line HIGH, while this one pictured is driving LOW, and you still have a conflict). Correct! For this reason I said in the RetroWiki forum, th...
by Silicebit.
Sat Jun 20, 2020 10:01 am
Forum: Hardware hacks and extensions
Topic: Erebus.
Replies: 6
Views: 1815

Erebus.

@kenneth. A proposal to improve Erebus for future batches :-) . You only need to add a resistor and, of course, modify the PCB.
I/O CONTROL Tristate.
I/O CONTROL Tristate.
Erebusdiagram2.jpg (584.01 KiB) Viewed 1815 times
by Silicebit.
Mon Jun 15, 2020 10:04 pm
Forum: Hardware hacks and extensions
Topic: Omnibus.
Replies: 7
Views: 2591

Re: Omnibus.

Nice project ! It could be interesting to put a diode for each connector on the i/ocontrol pin, that will avoid the level conflict. This will allow the interfaces to exploit its memory area on page 3, if the result is not convincing, we can provide a parallel bridge at each diode. 8) Feasible, but ...
by Silicebit.
Mon Jun 15, 2020 10:02 pm
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

I guess Dbug can be speaking about a thing like the Tandy color computer multi-pak interface. In my mind too. :)

http://www.trailingedge.com/trs80/Coco-Multi-Pakom.pdf
by Silicebit.
Sun Jun 14, 2020 6:08 pm
Forum: Hardware hacks and extensions
Topic: Omnibus.
Replies: 7
Views: 2591

Re: Omnibus.

With Omnibus we’ll have to be more careful. For example, we can't plug the Microdisc controller and Erebus at a time, both devices have an EPROM and both put low level in the /ROMDIS line. Two EPROMS at a time will not work.
by Silicebit.
Sun Jun 14, 2020 5:38 pm
Forum: Hardware hacks and extensions
Topic: Omnibus.
Replies: 7
Views: 2591

Omnibus.

The schematic diagram of Omnibus is finished!!
Omnibus schematic.
Omnibus schematic.
OmniBus.png (43.62 KiB) Viewed 2591 times
Now, I must to design the PCB. :)
by Silicebit.
Sun Jun 14, 2020 5:25 pm
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

The diode is a good solution if Erebus is the only totem-pole output in the I/O control line, or if it's in parallel with tri-state or open collector outputs. If there is another totem-pole output on the same line, the short circuit will appear again. :( TotempoleDiode1.png Of course, we can add ano...
by Silicebit.
Sat Jun 13, 2020 12:12 pm
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

The PAL16L8 in Protek interface has tri-state outputs, no problem here, but we must check if the I/O CONTROL output is put in high impedance mode when the Protek interface is not addressed. I still don’t know how the Protek interface works. The I/O CONTROL line is driven by the output of a 74LS30 in...
by Silicebit.
Wed Jun 10, 2020 4:10 pm
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

Great ! Will you build some to sell them ? I'll order the standar quantity (10 PCBs), one of them for me, and I’ll sell the rest. ... does the omnibus also powers the Oric itself so basically we just need to power the omnibus and everything else is properly powered? If yes, how would that work with...
by Silicebit.
Sat Jun 06, 2020 8:52 am
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

Omnibus has its own linear regulator, it can supply up to 1.5Amp, and the input is protected against polarity inversion. You just need an external PSU, (7.5v to 9V 2.5Amp).
by Silicebit.
Thu Jun 04, 2020 7:12 pm
Forum: Hardware hacks and extensions
Topic: Protek joystick interface diagram ?
Replies: 30
Views: 7820

Re: Protek joystick interface diagram ?

I saw something about the Protek components... The two chips named pal16L8 needs 210mA each and the little Ram 50mA That means around 500mA required for the Protek interface, I think it's too much to be added with the 250mA for Erebus and 650mA for the Oric computer. Yes too much, but the PAL16L8 c...
by Silicebit.
Fri May 29, 2020 10:41 am
Forum: Hardware hacks and extensions
Topic: IJK interface diagrams.
Replies: 106
Views: 59954

Re: IJK interface diagrams.

I wonder how difficult it would be to design an expansion for the Oric, which basically would be like a variant of the amplibus/cumulubus that you attach at the back of the oric, with multiple connectors on it ....... I’m working on a device I call OmniBus, this is an AmpliBus multi port with 4 exp...