ZX81CCP

ZX80 / ZX81 hardware and software offered for sale or swapping
Lardo Boffin
Posts: 622
Joined: Sat Nov 26, 2016 1:42 am

Re: ZX81CCP

Post by Lardo Boffin » Sun Apr 02, 2017 7:42 am

Now that you have a green one have you considered doing a red one as well? Green for issue one zeddys and red for issue three? :lol:
ZX81 iss 1 (bugged ROM, kludge fix, normal, kit)
Iss 3 with ZXVid, another in nearly perfect box
TS 1000 iss 3, ZXPand AY, ZX8-CCB & ZX-KDLX
TS 1500
TS 2000
Spectrum 16k (iss 1 s/n 1499)
Spectrum 48k
Toastrack + DIVMMC future

Moggy
Posts: 1504
Joined: Wed Jun 18, 2008 1:00 pm

Re: ZX81CCP

Post by Moggy » Sun Apr 02, 2017 4:22 pm

Lardo Boffin wrote:
Sun Apr 02, 2017 7:42 am
Now that you have a green one have you considered doing a red one as well? Green for issue one zeddys and red for issue three? :lol:
I bet you'll end up collecting the bloody lot!! :lol:

Lardo Boffin
Posts: 622
Joined: Sat Nov 26, 2016 1:42 am

Re: ZX81CCP

Post by Lardo Boffin » Sun Apr 02, 2017 8:49 pm

Moggy wrote:
Sun Apr 02, 2017 4:22 pm
Lardo Boffin wrote:
Sun Apr 02, 2017 7:42 am
Now that you have a green one have you considered doing a red one as well? Green for issue one zeddys and red for issue three? :lol:
I bet you'll end up collecting the bloody lot!! :lol:
Who? Me? :)
ZX81 iss 1 (bugged ROM, kludge fix, normal, kit)
Iss 3 with ZXVid, another in nearly perfect box
TS 1000 iss 3, ZXPand AY, ZX8-CCB & ZX-KDLX
TS 1500
TS 2000
Spectrum 16k (iss 1 s/n 1499)
Spectrum 48k
Toastrack + DIVMMC future

User avatar
blittled
Posts: 162
Joined: Fri Dec 19, 2008 2:04 am
Location: Northwestern Pennsylvania, USA

Re: ZX81CCP

Post by blittled » Tue Apr 04, 2017 2:21 am

I'm thinking or wiring a mini spst toggle switch to J7 and mounting it to the side of the case so I can easily reverse the screen :)
2X Timex Sinclair 1000, ZX81, ZX80Core, 5X 16K Ram Pack, ZXBlast, ZX P file to Ear Input Signal Converter, Elf II

User avatar
msansom
Posts: 37
Joined: Thu Feb 09, 2017 1:38 am

Re: ZX81CCP

Post by msansom » Wed Apr 05, 2017 4:28 am

blittled wrote:
Tue Apr 04, 2017 2:21 am
I'm thinking or wiring a mini spst toggle switch to J7 and mounting it to the side of the case so I can easily reverse the screen :)
What would really be cool would be to have a flip flop and address decode to put that under software control.
I'd like to say thank you on behalf of the group and ourselves and I hope we've passed the audition.

User avatar
PokeMon
Posts: 2128
Joined: Sat Sep 17, 2011 5:48 pm

Re: ZX81CCP

Post by PokeMon » Wed Apr 05, 2017 9:13 am

Andy's ZX ULA is able to do that and offers much more like clock doubling. Unfortunately is not available now. Anyway not fun to solder 10 or more wires instead of now only 3 (GND,5V,Video In) and board wouldn't be so tiny.

User avatar
siggi
Posts: 752
Joined: Thu May 08, 2008 8:30 am
Location: Dauernheim, Germany
Contact:

Re: ZX81CCP

Post by siggi » Wed Apr 05, 2017 10:32 am

Here you can see what is necessary to have some additional flipflops for some switching activities (ram bank switching)

http://forum.tlienhard.com/phpBB3/viewt ... 561#p27216

green: 8 addressbus lines
yellow: 8 databus lines (OK: sufficient would be 1 for your single flipflop)
blue: control bus

Regards
Siggi
My ZX81 web-server: online since 2007
http://zx81-siggi.endoftheinternet.org/index.html

User avatar
gammaray
Posts: 247
Joined: Sun Apr 17, 2016 1:44 am
Location: Texas

Re: ZX81CCP

Post by gammaray » Thu Apr 13, 2017 10:44 pm

Wonderful improvement! Now, how about a frame buffer to hold the screen until display can be executed?
By Pokémon:
I made a study about that earlier already and have a solution in my mind but in the moment no chance to realize. Anyway would be larger in size and more expensive. I have another solution in my mind which may come in summer. Maybe. ;)
Pure sorcery! :twisted:
Finish what you start. Truth is over the mountaintop or six feet under.
4 x TS1000, 2 x TS1500 , 2 x timex 2040 printer, 1/2 x timex 2020 cassette deck, ZXPAND, ZeddyNET, ZXBlast..., unfinished Spectrum...

User avatar
blittled
Posts: 162
Joined: Fri Dec 19, 2008 2:04 am
Location: Northwestern Pennsylvania, USA

Re: ZX81CCP

Post by blittled » Sat Apr 15, 2017 1:59 am

What size Phillip Screw driver is used on the pots. Is it a 0#, 00#, 1#,etc? I need to make an adjustment and all my small screwdrivers won't work well.
2X Timex Sinclair 1000, ZX81, ZX80Core, 5X 16K Ram Pack, ZXBlast, ZX P file to Ear Input Signal Converter, Elf II

User avatar
gammaray
Posts: 247
Joined: Sun Apr 17, 2016 1:44 am
Location: Texas

Re: ZX81CCP

Post by gammaray » Sat Apr 15, 2017 3:24 am

blittled wrote:
Sat Apr 15, 2017 1:59 am
What size Phillip Screw driver is used on the pots. Is it a 0#, 00#, 1#,etc? I need to make an adjustment and all my small screwdrivers won't work well.
Try this...
http://sinclairzxworld.com/viewtopic.ph ... =30#p21770
Finish what you start. Truth is over the mountaintop or six feet under.
4 x TS1000, 2 x TS1500 , 2 x timex 2040 printer, 1/2 x timex 2020 cassette deck, ZXPAND, ZeddyNET, ZXBlast..., unfinished Spectrum...

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest