Search found 518 matches

by iss
Fri Dec 15, 2017 11:21 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

20171216_000215.jpg ... and here is the short clip: https://youtu.be/W6KxqdzQLX8 What is new: I connected the SYNC output to the TAPE input (i.e. the famous VSYNC hack ;)) to filtrate H-sync pulses and left only V-sync to be used for synchronization. In the video I manually connect and disconnect t...
by iss
Fri Dec 15, 2017 5:33 pm
Forum: 6502 assembly coding
Topic: Identifying Oric-1
Replies: 3
Views: 43

Re: Identifying Oric-1

Take a look in Atmos ROM disassembly: http://www.defence-force.org/ftp/oric/documentation/v1.1_rom_disassembly.pdf There are lot places marked with V1.0 and V1.1 which show differences in both versions - most are in page 2. If the question is exactly for a zero page address then you can use $31 - Sc...
by iss
Wed Dec 13, 2017 10:52 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

20171213_231329.jpg This is today's best result. :) We are getting closer and closer.... For now I have the same results with extra ULA and without it, so which is better - I still don't know. About the video mixer - having an emulator for experiments and development will be really great! Else I th...
by iss
Tue Dec 12, 2017 1:21 am
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Additionally I made one quick and dirty ROM for testing. On the pictures above you see vertical lines - it's not coincidence! Attached are the sources, 4k and 2k ROM files. You can load them in Oricutron - edit 'oricutron.cfg' and set the 4k file as atmos rom or the 2k file as microdisk rom then sta...
by iss
Tue Dec 12, 2017 12:59 am
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

For all impatient Oric maniacs: 20171212_010731.jpg 20171212_010900.jpg 20171212_003338.jpg ... and two short clips: https://youtu.be/2FSEukwxqn4 https://youtu.be/IO6X_84h6U0 Far far from working, but things are looking optimistic. Unfortunately I think that something on the upper board died during ...
by iss
Fri Dec 08, 2017 10:59 am
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Clipboard01.jpg Clipboard02.jpg Clipboard03.jpg Well, this are samples with the changed schematic (AND instead NAND), now the reference SYNC is BEHIND the derived SYNC's with exactly 1 full period, so no big difference and in common it doesn't matter which variant will be used. For me the important...
by iss
Thu Dec 07, 2017 8:47 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

@NigthBird: No, I don't think this simplification will work. After the XOR we must have NOT to invert the logic and enable the clock only when the clocks are the same . BUT , (looking again at the traces) if we change the NAND to AND (7400 -> 7408) then maybe the 1/2 cycles delay will be eliminated...
by iss
Thu Dec 07, 2017 11:27 am
Forum: Games
Topic: Blake's 7 feedback and review thread
Replies: 98
Views: 4533

Re: Blake's 7 feedback and review thread

Attached is 'Floppy.cpp' from the SVN with fixed CRC. I added missing 'compute_crc' calls where they are needed.
Floppy.cpp.zip
(8.83 KiB) Downloaded 7 times
by iss
Wed Dec 06, 2017 1:29 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

At end one interesting case ! Clipboard04.jpg Clipboard05.jpg Here, after power-on the reference ULA started with 60Hz but the child ULA's with 50Hz. This actually confirms that the synchronization logic works :). To not happen such case, the reference ULA should be fed with proper data to initializ...
by iss
Wed Dec 06, 2017 1:10 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Clipboard02.jpg
Clipboard03.jpg
On the traces CLK, CLK1,CLK2,CLK3 are 12Mhz clocks and VSYNCH/HSYNC are visible.
You can see how the reference SYNC is 1/2 of the 12MHz period before the child's SYNCH's.
I think It's worth to sacrifice one ULA as reference.
(continue below...)
by iss
Wed Dec 06, 2017 12:40 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Hello all! Below are updated schematic and test results. I think we have working synchronization :) sch.jpg 20171206_014751.jpg In short how it works: I used one ULA (U2) as reference, its SYNC signal is compared with the SYNC form a "child" ULA (U5,U6,U7), so if both SYNC's are the same then the cl...
by iss
Thu Nov 30, 2017 9:09 pm
Forum: Hardware hacks and extensions
Topic: And now, box for the controller.
Replies: 7
Views: 830

Re: And now, box for the controller.

The Good, the Bad and the Ugly :) 20171130_213534.jpg 20171130_213704.jpg 20171130_213745.jpg I started with the right one using ABS material, but the result was extremely fragile - the supports broke before printing was finished. The left and the middle boxes are from PLA material and they are real...
by iss
Thu Nov 30, 2017 12:26 pm
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Is the printer port bi-directional? I thought it could only send data. I'm sure you know this well ;), it's bi-directional, every bit can be set independently as IN or OUT, think about the joysticks... About the RAM overlay - if it's requirement then maybe microdisc for every machine is best choice...
by iss
Thu Nov 30, 2017 10:37 am
Forum: Technical questions
Topic: Merging video output?
Replies: 46
Views: 2155

Re: Merging video output?

Yep, I think the parallel port is the best option for communication between machines - easy to drive and no additional hardware. Maybe it will be better to use it as kind of (a)synchronous serial interface with two lines STB (for output) and ACK (for input), emulating something standard as protocol ...