News:

Printed Amstrad Addict magazine announced, check it out here!

Main Menu

Recent posts

#91
N
Emulators / Re: ZEsarUX 11
Last post by Neville - 15:02, 11 June 24
Nevermind. I found the option to use keyboard as a joystick on Settings --> Hardware. But since I already made a fool of myself, could you allow Left CTRL and Left ALT as fire buttons too? Right CTRL and ALT work great, but those are even better.
#92
avatar_roudoudou
Emulators / Re: ACE for Linux,Mac, Windows...
Last post by roudoudou - 14:50, 11 June 24
Quote from: ago on 13:37, 11 June 24Is there a full screen option???

I cannot find it ???


nope, do not want to spend my time on windows troubles (+there is kind of impossibility to intercept special keys without OS specific code => again, 3x the dev time)
#93
Quote from: jelcynek on 12:09, 11 June 24Nevermind. I just realized there is other pin connected to the GND in the flyback. So I suppose that big wire was only to keep the flyback in place.


Or to give it a direct path to the metal frame (and earth) in case there's a short and extremely high current burns the tracks off the PCB? Is there a picture of the mystery "big wire" somewhere?

Bryce.
#94
N
Emulators / Re: ZEsarUX 11
Last post by Neville - 13:58, 11 June 24
Are you the author? Wow. In that case I'd like to request joystick emulation through the keyboard.

Unless it already exists and somehow I managed to miss it. Something simple would suffice, something like using the keypad with the num. block. on.
#95
avatar_ago
Emulators / Re: ACE for Linux,Mac, Windows...
Last post by ago - 13:37, 11 June 24
Is there a full screen option???

I cannot find it ???
#96
avatar_Bryce
Amstrad CPC hardware / Re: Slightly different take on...
Last post by Bryce - 12:26, 11 June 24
Quote from: Benedikt on 21:08, 10 June 24Before you do your old mod all over again, you could try to weaken the 220Ω resistor between Gate Array and /SYNC output by e.g adding another 220Ω resistor in parallel.

If we assume that the Gate Array outputs behave roughly like normal TTL outputs, their High level should be roughly 3.6V.
The 220Ω resistor in series and the 75Ω input impedance of the RGB blanking input mean that the latter only sees at most (75Ω / (75Ω + 220Ω)) * 3.6V = 0.68V.
That is without the capacitor that is supposed to turn the /SYNC signal into a DC voltage.
If we assume in our back-of-the-envelope calculation that the HSYNC pulse takes 16 out of 1024 pixel clocks per line and that the VSYNC pulse is 16 lines long, we loose roughly 6.7% of the above.
We then end up with 0.63V, which is way below the 1V to 3V specified in EN 50049-1 "Peritelevision connector" for a logical "1" and very close to the 0V to 0.4V specified for a logical "0".
Even if the Gate Array's High level is 5V, we still only get a filtered DC voltage of 0.88V.

With the additional 220Ω resistor in parallel, we should get at least (75Ω / (75Ω + 1 / (1 / 220Ω + 1 / 220Ω))) * 3.6V * 93.3% = 1.36V.
The combined resistance of 110Ω instead of 220Ω still limit the base current of the KTC1815 NPN transistor in the GT65 to a bit less than the specified maximum of 50mA.
You could therefore use the CPC with the additional resistor with both, the GT65 and a SCART TV set, respectively.

Very nicely calculated. The bit that's missing is the capacitor, which is extremely difficult to calculate, but it's buffering will have an additional positive effect on the RMS value of the PWM signal. You still wouldn't have a 100% accurate answer though, because the GND of both devices won't be exactly equal, so measuring the pin voltage (or just trying it out) is the only real way of knowing if it will work with a particular TV or not. I did mention above that it doesn't work on all TV's, however, but I found it worked on the majority of them, mainly due to the fact that early SCART TV's were built with discrete components and anything even slightly above 0.4V was considered to be a 1. Later TV's had more integration or even a "SCART chip" and were much more fussy about the voltage levels. So the older the TV, the more likely it is to work.

Bryce.
#97
Nevermind. I just realized there is other pin connected to the GND in the flyback. So I suppose that big wire was only to keep the flyback in place.
#98
C
Emulators / Re: ZEsarUX 11
Last post by chernandezba - 12:09, 11 June 24
Quote from: Neville on 12:22, 07 June 24Big fan of this project, especially since the author added PCW emulation. We don't have enough Amstrad PCW emulators.
Thanks! :)
#99
Quote from: darkhalf on 09:49, 25 January 24With flybacks there is a place Tulli Electronics which has these for a decent price. These are the last (in the world!) that I know exist and there appears to be 3 remaining
https://www.tullielettronica.net/prodotti/hr6355-145961.aspx
So my money is on flyback, given I've had to replace 3 in monitors in the last year. The coils vibrate, enamel flakes and they short out

darkhalf you replaced flybacks for the ones from the Tulli Electronics? I wonder, because the one from the Tulli Electronics doesn't have that thick wire which was connected originally to the Ground. How did you managed that? Was it only to keep flyback in place?
#100
avatar_abalore
Programming / Re: 1 pixel horizontal hardwar...
Last post by abalore - 11:29, 11 June 24
Yes, my way to proceed in cartridge games is compiled sprites and clean background buffer (as in Alcon)
Powered by SMFPacks Menu Editor Mod