Search found 197 matches

by zsolt
Sat Nov 16, 2019 12:05 am
Forum: Hardware
Topic: RAMPACK and Hi-RES mod ?
Replies: 19
Views: 830

Re: RAMPACK and Hi-RES mod ?

bola_dor wrote:
Thu Nov 14, 2019 11:53 pm
... (I post here my own diagram from about 30years ago) RAM used are 2x 6264 ...
It is OK, just do not use the /RD line (remove/disconnect from pin 22 of 6264).
and connect pin 22 to pin 20 (/OE to /CS)
and connect pin 22 to pin 20 (/OE to /CS)
by zsolt
Tue Nov 12, 2019 1:13 pm
Forum: Hardware
Topic: RAMPACK and Hi-RES mod ?
Replies: 19
Views: 830

Re: RAMPACK and Hi-RES mod ?

Is a NOT gate and the rectangles ar the two ICs mounted on top the other :o :? Yes - sorry for the sketch, just the Excel was at hand. About the "without components" mod.. I have some doubts I marked on the picture.. Purple arrow: is the thick way cutted ? Green arrow: are the three leads soldered ...
by zsolt
Mon Nov 11, 2019 5:21 pm
Forum: Hardware
Topic: RAMPACK and Hi-RES mod ?
Replies: 19
Views: 830

Re: RAMPACK and Hi-RES mod ?

For the two SRAMs I would use this schematic rather
(the /RFSH is not necessary, can be VCC)
(the /RFSH is not necessary, can be VCC)
and i am using this for TS1016
Regards,
Zsolt
by zsolt
Wed May 22, 2019 4:26 pm
Forum: ZX BASIC
Topic: ZX81X2.ROM - and the big bang
Replies: 36
Views: 9535

Re: ZX81X2.ROM - and the big bang

Sorry for this long silence - I was on a (very) long weekend in Barcelona. :D The original CLS (more exactly the LOC-ADDR ) routine uses the sv. VARS as a pointer, from which it is searching and counting backward the N/L characters (24+1) to get exact line address. So it skips those 32 extra bytes ....
by zsolt
Tue May 14, 2019 9:26 pm
Forum: ZX BASIC
Topic: ZX81X2.ROM - and the big bang
Replies: 36
Views: 9535

Re: ZX81X2.ROM - and the big bang

Dear Siggi and Joachim, Did you know that the d-file of your program is longer than should be? :o It contains 32 extra bytes after the latest N/L character in front of the beginning of the variables. Sysvar D_FILE ($400C) points $40F3, and the VARS ($4010) points $442C. The difference is $0339 (825 ...
by zsolt
Tue Dec 25, 2018 12:06 pm
Forum: Welcome Area
Topic: Merry Xmas and Happy Holidays
Replies: 9
Views: 2751

Re: Merry Xmas and Happy Holidays

Merry Christmas to all,
Zsolt
by zsolt
Sun Nov 11, 2018 6:44 pm
Forum: ZX BASIC
Topic: SPeccy ON the ZeddY
Replies: 100
Views: 31501

Re: SPeccy ON the ZeddY

Hi Siggi, No, these are ZX81-specific patterns, but ... In SPONZY they are available as UDGs ( chr$ 144 ... chr$ 164 ), which are defined during the startup: L0000: out ($FD),a ; Switch NMI off! LD DE,$FFFF ; Set pointer to top of possible physical RAM. JP L11CB ; Jump forward to common code at STAR...
by zsolt
Fri Nov 09, 2018 1:51 pm
Forum: ZX BASIC
Topic: SPeccy ON the ZeddY
Replies: 100
Views: 31501

Re: SPeccy ON the ZeddY

Hi,
siggi wrote:
Fri Nov 09, 2018 11:05 am
And is it not possible to have only one rom (including Erik's patches)?
It is more than possible :D just use the sponzy2018.rom above - it contains Erik's patch.
Regards,
Zsolt
by zsolt
Thu Nov 08, 2018 5:12 pm
Forum: ZX BASIC
Topic: Possible bug in ZX81x2 ROM ?
Replies: 36
Views: 6335

Re: Possible bug in ZX81x2 ROM ?

Moggy wrote:
Fri Nov 02, 2018 8:58 pm
Slow down Zsolt I'm running out of EPROMS!! :lol:
Sorry Moggy, here is a newer one. :lol:
Zsolt
by zsolt
Thu Nov 08, 2018 5:00 pm
Forum: ZX BASIC
Topic: ZX81X2.ROM - and the big bang
Replies: 36
Views: 9535

Re: ZX81X2.ROM - and the big bang

Hi, I have made some changes in the 'series generator' routine. In the 1st round of the generator loop the operands (and the results too) were zeros. The improved version skips this 1st round, so saves some times: ; ; The initialization phase. ; .db $3A ;;mul-by-2 2*x DEFB $C0 ;;st-mem-0 2*x DEFB $0...