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Problem SpeccyNot sure anyone can help without a photo but I'll describe it anyway (and maybe post a photo later). I have a problem speccy. The display shows a bo…
... Z80 getting a reliable clock signal, do the address lines look like ... -
Problem SpeccyNot sure anyone can help without a photo but I'll describe it anyway (and maybe post a photo later). I have a problem speccy. The display shows a bo…
... Z80 getting a reliable clock signal, do the address lines look like ... -
50p on your phone billThe UK government [I]really[/I] know how to put the 'S' into Stealth Tax: [URL="http://news.bbc.co.uk/1/hi/technology/8102756.stm"]http://news.bbc.c…
... being without a mobile ! I do divert it to my landline ... trying to get a signal !
Do agree with people in ... -
+3 dead(!)Hi, When I turn on my +3 I see only white and black strips (vertical) on screen any idea on how to fix it? Thank you in advance Chris [IMG]http:…
... ...
BTW: check the INT signal at Z80. Is it pulsing ... -
+3 dead(!)Hi, When I turn on my +3 I see only white and black strips (vertical) on screen any idea on how to fix it? Thank you in advance Chris [IMG]http:…
... ]
....
BTW: check the INT signal at Z80. Is it pulsing ... change?[/QUOTE]
the INT is pulsating (high).
There ... -
RFC: ZXI hardware interface standardisationReposted from c.s.s to reach a wider audience [QUOTE=Andrew Owen] You may have noticed that there are more people making add-ons for the Speccy than…
... it?
- INT triggering. Not many devices uses ... straight connection from the INT signal at the rear bus, ... device to use the INT signal? If it's the ... the M1 signal and/or the RFSH signal, so misdecondings ... be ZXI compliant? The signal is documented to be ... -
Beebs Back in Education AgainBletchley Park Museum of Computing is running classes for A-Level students in computing using old BBC-Bs: [URL="http://www.bbc.co.uk/news/technology-…
... submitting a program with the INT command we had not used ... by asking 'What does the INT command do then?' I told him ... -
Development choices, help!As a small part-time project I would like to convert my daily programming work (a workflow/bpel engine) to the Spectrum, purely for fun. I would like…
... I'm sure you can do it better :) And no, the ... /> char get_ch()
{
int ch;
do
{
ch ... -
writing an emulator-newbie needs helpHi, this is my first post here. I decided to write a minimalistic emulator of ZX Spectrum-no emulation of advanced peripherals, no emulation of sound…
... bad things would happen if EI enabled interrupts right away? I ... interrupt handling routines end with EI and RET instructions, but why ... would accepting an interrupt between EI and RET be so dangerous ... right. And, yes, people who do EI;RET are doing it wrong ... -
SPECTRA New from Paul FarrowLooks good! Read about it [URL="http://www.fruitcake.plus.com/Sinclair/Spectrum/Spectra/SpectraInterface.htm"]here[/URL]
... that clock and the 50Hz INT signal would be enought to keep ... -
recovering the stack after an errorMy normal error handler starts with the stack as reset by LD SP,(ERR_SP) in $0053 ERROR_2, sets up some stuff and returns to BASIC via a "JP C,$1e73 …
... it should if you omit EI (after executing FOR loop, of ... i setupped to pop on EI) is not popping. so 48k ... BEEP command, for example, can do EI. maybe some others. give us ... -
WIP: ULAPlus hardware implementationThis aims to be an "almost" plug-in replacement for the Sinclair ULA chip fitted in Spectrum 16K/48K/Plus machines. It comes in a form of a small PC…
... just a little bit the INT signal (try to delay it by ... -
WIP: ULAPlus hardware implementationThis aims to be an "almost" plug-in replacement for the Sinclair ULA chip fitted in Spectrum 16K/48K/Plus machines. It comes in a form of a small PC…
... just a little bit the INT signal (try to delay it by ... -
Altera CPLD vs Xylinx FPGAI will dig into the world of FPGA's, mainly to find something that can replace one or more GALs for my current and new projects. And it's never bad t…
... input clk, // connected to INT signal (20ms period)
input ... /> .clk(clk), // 50Hz (INT) signal
.enautofire(enautofire), // the ... .firein(fire), // fire signal from joystick
.fireout( ... -
Spectrum +3 to Joytech PS2 8" LcdHi, I?m making some cables so I can connect my old computers to a Joytech PS2 8" Lcd. Starting with my Spectrum +3 I made a RGB and a composite cab…
[QUOTE=orange;676123]perhaps there is not enough voltage on "Pin 16 Blanking signal up"[/QUOTE]
No needs that signal, besides that in composite signal do the same problem -
SPECTRA - RGB SCART Interface for 48K SpectrumSince the launch of the SPECTRA interface back in June 2012, some discussion of it has appeared in the forums in the past (mainly [URL="http://www.wo…
... non standard kind of YPrPb signal. First, the Y component is ... its clear input with the INT signal), and changes its output with ... -
WAV filesI have tried Google bot so far no real luck. But are there any sites oyut there that has got ZX Spectrum game files in WAV format? I can of course t…
Tapir, available from this site. Works brilliantly! Just select "Play to WAV" from the pull down.
[url]http://newton.sunderland.ac.uk/~mikie/[/url] -
Using the stack to blit bufferI was using a ldir to blit my back buffer to the screen RAM, and it was working pretty well if not rather slow. After reading about using the stack …
... doesn't even include an 'EI' to ensure the next ... with the TV frame you do EI then HALT.
... it's much easier to do it this way than ... your timing-critical code to do something slightly different from one ... then don't forget an EI just before you RET ... -
Pentagon floating bus timingI wanted to take a little break from working on the ZXDS UI yesterday, so I added support for Pentagon timing instead, so I can finally enjoy the lik…
... short notice: The "length of INT-signal" is usually adjusted quite manually ... -
Pentagon floating bus timingI wanted to take a little break from working on the ZXDS UI yesterday, so I added support for Pentagon timing instead, so I can finally enjoy the lik…
... short notice: The "length of INT-signal" is usually adjusted quite manually ... -
New test for finding missing +2A/+3 ULA timing detailsHello, having added the +2A/+3 emulation recently, I want to make sure I got the ULA timing 100% right. We know when the contention pattern starts, …
... the CPU sometimes samples the /INT correctly during the first cycle ... internal microschema for sampling the /INT signal inside the CPU, and ... combined leads to the different INT durations reported, and the ... they can detect the /INT early at all times...
Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... solder etc.) somewhere between the INT signal and one of the outputs ... LS32.
So IMHO the INT signal should be checked with and ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... solder etc.) somewhere between the INT signal and one of the outputs ... LS32.
So IMHO the INT signal should be checked with and ... nothing changed.:confused:
INT Signal shows 5V with slow pulse ...cause of 1 tstate differencethe sinclair faq, located at: [url]http://www.worldofspectrum.org/faq/reference/48kreference.htm[/url] says: "NB: Investigations in May 2004 have rev…
... both the shape of the INT signal and the sensitivity of the ...Composite video ghost image on ZX Spectrum 128K +2Hi, I have a ghost image on the composite video out on my ZX Spectrum 128K +2 and have run out of ideas of what could be wrong. Does anybody have a…
... need any diodes for brigth signal using a gray +2 as ... from bad synchronisation. So the signal on pin 21 of the ... plug should be observed. What signal do you connect to pin 21 ...Spectrum +2 (grey): Mod- and operation- related advices needed.Dear Sirs and Ladies, Please welcome a newbie to the “World of Spectrum” (both to the forum and, well, metaphorically). I’ve recently purchased a…
But still - what signal do I have to conjure to feed the ULA?
