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#1
Quote from: BSC on Yesterday at 12:46I did my fair amount of experiments with the AY in the last 10ish years and it never occurred to me that what you claim here is possible. At least not without glitches, on a real machine.
If it is possible on real hardware to send values continuously, there will be glitches (I know the term hazard for this). E.g. while switching between register selection and register update, if the PPI is not programmed to stop it will send the next register index also as register value for the last register index. For operation in music trackers where all or at least several registers are updated in a row this clearly needs to be considered.
But while playing a sample, only a single register is changed. If there is a glitch/hazard in the value, there will be a minimal creaking in the output until the right volume value arrives. But here we are talking about microseconds. Is this audible?
One detail question we can think about: The tone frequency of a channel is divided into two registers. What happens if one updates the first register, but is not fast enough to update the second? Does the PSG stops counting during these operations? Or does it simply continue and possibly will output a wrong frequency until the second register is also updated? Usually the ICs used back then do not contain buffers, caches, or complex internal logic, but simply do their main work and rely on a bit good will of the surrounding (e.g. timing).
#2
Quote from: McArti0 on Yesterday at 11:22Quote from: Targhan on 20:15, 12 May 25Does any emulator show this?Quote from: andycadley on 12:38, 12 May 25I have a sneaking suspicion you may not get audio on a Plus machine if you don't,Yup, you're right!
It would be a very absurd design. Blocking the F4 port to switch something in F6? After all, AY works the same way.
I tried on WinAPE. Configured to 6128 and 6128 plus it did not show a difference. In both cases it works. Would be good to know how different actual hardware behave.
@Targhan : Does "Yup, you're right!" mean: "I got the same feeling. I agree with this." Or does it mean: "I tried this on real hardware. It did not work as expected."
#3
Technical Support - Software related / Re: FAT handling in AcmeDOS
Last post by Emu - Yesterday at 23:28@Prodatron : I have managed to make AcmeDOS work (FAT16 with a cluster size of 2048). However, I still need to provide the root directory in sector 497 (whereas your formatter uses 513). I wonder if anyone has ever checked if the X-Mass DoM really has a volume label "PQI IDE" after using your formatter or if sector 513 is used as a regular data sector by AcmeDOS (thus overwritten by files after some time) and the root directory (sector 497) is just empty after formatting. Could the volume label be read from AcmeDOS at all?
#4
C
General Discussion - Introductions / Re: FUN FACT: Amstrad was the ...
Last post by cwpab - Yesterday at 22:43A couple of thoughts:
- In the "1 year hands-on experience" article I linked in my last message, the guy says he bought the Amstrad PCW16 in 1999, and he had been using it since then. So his lenghty and enthusiastic review was very likely written around the year 2000 (which means he could not have "nostalgia" for the machine). He also says he "only has a few GB of data in Windows", which is consistent with that period.
- I'd like to see games for the PCW16, making use of the whooping 16mhz Z80.
- In the "1 year hands-on experience" article I linked in my last message, the guy says he bought the Amstrad PCW16 in 1999, and he had been using it since then. So his lenghty and enthusiastic review was very likely written around the year 2000 (which means he could not have "nostalgia" for the machine). He also says he "only has a few GB of data in Windows", which is consistent with that period.
- I'd like to see games for the PCW16, making use of the whooping 16mhz Z80.
#5
NC100, NC200, PCW, PDA600 - the rest of the Family! / Re: PCWwiki
Last post by jevicac - Yesterday at 21:09Good evening, good news for PCWers. We've preserved two new games that are very difficult and expensive to obtain. The first is Orphee (French), and you can see some screenshots of them on the PCWWiki.
https://www.habisoft.com/pcwwiki/doku.php?id=es:juegos:orphee_voyage_aux_enfers
On the other hand, ACADEMI (Tau Ceti II) will not yet be available for download.
They will not yet be available for download.
https://www.habisoft.com/pcwwiki/doku.php?id=es:juegos:orphee_voyage_aux_enfers
On the other hand, ACADEMI (Tau Ceti II) will not yet be available for download.
They will not yet be available for download.
#6
This is THE option for me. Loads super fast and plays very well. No loading times. Run perfectly from files, perfectly!
#7
The Spacebar is normally mapped as the fire button for keyboard users, but I can tinker something I guess.
I've got a question regarding the Ulifac/Usifac. From what I've understood (correct me if I'm wrong), you can use it kinda like a hard drive, or rather a SSD. So would it be possible to create a Turrican folder on the SD card, and copy all the game files in it?
I only use emulators, so it's a bit abstract to me. I'm joining the game files in enclosure.
I've got a question regarding the Ulifac/Usifac. From what I've understood (correct me if I'm wrong), you can use it kinda like a hard drive, or rather a SSD. So would it be possible to create a Turrican folder on the SD card, and copy all the game files in it?
I only use emulators, so it's a bit abstract to me. I'm joining the game files in enclosure.
#8
These things are always a trade off. Zilog intended the alt registers to be a kind of early version of "supervisor" mode, so an OS could be more isolated. It's not surprising people used it like that.
#9
Quote from: GUNHED on 22:17, 11 May 25The origin of this evil is that the coders of the firmware came from the 8080 (that's what they told by themselves actually). There is some article somewhere (google it).1. There's plenty of Z80 code in both the firmware and BASIC. And it's very skillfully done.
The CPC has 300 interrupts per second. This means roughly, between two interrupts there are 3300 us or NOPs. Wasting the 2nd register set for interrupts only gains one of two dozens of NOPs. Not even 1%!!!
2. The alt registers cache video mode and ROM enable states (plus the I/O port). ROM enable states get changed every time you call into the firmware. That could be happening thousands of times per second. They've actually made very clever use of niche features of the Z80 (which *aren't* in the 8080) to make the machine faster.
PS. Happy to have a polite discussion. If this starts an argument I'll avoid the thread.
#10
@Jean-Marie
I also run the print commands and I get the same values as in the screenshot you attached.
I also run the AMSDOS image and ... SUCCESS! And this is just a beauty.
One recommendation, is it possible to map the action button that is currently on the Return key to Spacebar instead? For those with one button joystick it is easier to extend your fingers and press spacebar.
I also run the print commands and I get the same values as in the screenshot you attached.
I also run the AMSDOS image and ... SUCCESS! And this is just a beauty.
One recommendation, is it possible to map the action button that is currently on the Return key to Spacebar instead? For those with one button joystick it is easier to extend your fingers and press spacebar.