Pin 10 of the ADC goes only to Pin 9 of the LS93.
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Search found 19 matches
- Mon Jan 29, 2024 11:07 am
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
- Sun Jan 28, 2024 7:17 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Hi, that's great - thanks again for the info and pics. It looks like the NAND gate is simply used as a buffer for the CPU clock signal and the rest of the inputs are pulled up via the 2K2 resistor. The adjacent cap now looks like a decoupling cap. Would you mind checking if pins 1 and 12 are connec...
- Sun Jan 28, 2024 6:52 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Yes, thanks. I didn't notice the grey band before, double checked and they are the same1024MAK wrote: ↑Sun Jan 28, 2024 6:02 pm If the diodes have the same colour bands (yellow, brown, yellow, grey) as the diodes on the bottom right on this ZX81 board, then they are 1N4148 diodes.
Mark
- Sun Jan 28, 2024 3:26 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Hi, that's great - thanks again for the info and pics. It looks like the NAND gate is simply used as a buffer for the CPU clock signal and the rest of the inputs are pulled up via the 2K2 resistor. The adjacent cap now looks like a decoupling cap. Would you mind checking if pins 1 and 12 are connec...
- Sun Jan 28, 2024 1:15 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Thanks for the all photos - they're really useful. I've created a first cut of a schematic https://github.com/ZXQuirkafleeg/ZX-Interspec/blob/main/Interspec%20v0.1.pdf . It's based your photos but there are a few gaps: 1) Diode types, cap values and tx types are all estimates. It would be good to g...
- Sun Jan 28, 2024 12:41 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Ah, Yes, I see now, sorry, no offence meant, just didn't spot the date. Wow, if only I had cleared the loft a couple of years earlier...
- Sun Jan 28, 2024 11:23 am
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
You seem to be just a few years too late. www.dcpmicro.com takes me to a new standard getting started Wordpress page, that does contain in the lower left corner: TOO LATE? - er that's why they call it RETRO COMPUTING nowadays :D Using the wayback machine https://web.archive.org/web/20230128190031/h...
- Sun Jan 28, 2024 7:21 am
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Hi Kiwi, Thanks for that. I'll take it to bits and see if I can help resolve the questions, certainly with the component types and values. :) Thanks for the all photos - they're really useful. I've created a first cut of a schematic https://github.com/ZXQuirkafleeg/ZX-Interspec/blob/main/Interspec%2...
- Wed Jan 24, 2024 11:27 am
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Here's some photos of the PCB and chips. I'm working on a reverse engineering diagram too. Hope they help you. https://i.postimg.cc/ctCt4dYC/PXL-20240117-143259862-MP.jpg https://i.postimg.cc/0rywC03v/PXL-20240117-143310858-MP.jpg https://i.postimg.cc/KRd3xSYc/PXL-20240117-143325749-MP.jpg https://i...
- Mon Jan 22, 2024 6:38 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
I've just uploaded the video to my YT channel, you can view it here:
Hope you find it useful
Hope you find it useful
- Sat Jan 20, 2024 7:56 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
OK, just spent many hours OCRing, editing and remaking the user guide. I've created a page about the INTERSPEC on my website so you can download a PDF version there. I'll be building a test rig and programs to test it with and putting my results there. Hope this helps more INTERSPEC users. https://c...
- Fri Jan 19, 2024 3:42 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
UPDATE: Thanks to that document via kiwi, I have begun basic testing of the module - IT WORKS! I managed to find a reference to the original documentation and I have now been sent a scanned copy. I'm in the process of OCRing it and will create a WORD / PDF version of it which I will share. I'm also ...
- Tue Jan 16, 2024 5:34 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
This is relevant to my interests so I'll be watching this thread with interest. I want to be able to do some simple home automation tasks, log temperatures etc. Does anyone know if there is any hardware documentation for this device? I'd love a circuit diagram to see how they did it. I don't suppos...
- Tue Jan 16, 2024 5:32 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Such a cool piece of equipment, the idea of being able to control something really appeals. I hope you get it up and running. I’ve long wanted to do a similar thing, maybe one day I’ll get around to it. I'm sure I will, somewhere in the boxes from my move 20+ years ago, the instructions are still t...
- Tue Jan 16, 2024 5:31 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Thanks for that too, very usefulKiwi wrote: ↑Mon Jan 15, 2024 11:02 pm And take a look at an old issue of ZX computing http://www.retro8bitcomputers.co.uk/Mag ... g&issue=14. Page 72 gives a review of the device along with a few basic programming examples.
- Tue Jan 16, 2024 5:00 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
There's a promo leaflet for the DCP devices here: https://forum.tlienhard.com/phpBB3/download/file.php?id=12348&sid=92531b17df02ac5071b7b2da0fa45324 One of the pages indicates the TTL port is at IN/OUT 95, the ADC is IN 31, Switch inputs at IN 63 and relay outputs at OUT63. You may be able to f...
- Mon Jan 15, 2024 7:09 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
Re: DCP Interspec BUS Expansion Adaptor
Found a pic of the interface and instruction sheet.
- Mon Jan 15, 2024 6:56 pm
- Forum: Hardware
- Topic: DCP Interspec BUS Expansion Adaptor
- Replies: 33
- Views: 1463
DCP Interspec BUS Expansion Adaptor
Hi all, I have one of the DCP Interspec BUS Expansion adaptors. It provides I/O functionality for the spectrum. You can read all about it here: https://spectrumcomputing.co.uk/zxsr.php?id=1000195 I used to use this to control Meccano models - switching motors and lights on and detecting switch senso...
- Mon Jan 15, 2024 6:37 pm
- Forum: Announcements
- Topic: Introduce yourself!
- Replies: 684
- Views: 188947
Re: Introduce yourself!
Hi I'm Chas, A retired TV engineer from the late 60s. Built a ZX80, then bought a speccy. Had an interface II, AMX Mouse, 2 x microdrives and wrote quite a few training manuals using TASWORD. Refitted the PCB into a full sized keyboard and it worked very well. Then I bought a PC. Boxed up the speccy...