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Re: Jupiter ACE (again)
Posted: Sun Sep 13, 2020 6:47 pm
by anightin
Now my edge connector boards are back and built, the Ace is now ready to expand!
I started with a 30cm cable as that's all I had spare, but if I can get it long enough I will move it to the other side of the case where the expansion slot hole is. I might get a 40cm cable and try that first.
The other end of the cable is connected to the Ace Bus via my other board which comprises a modified ZX81 edge connector to 50 way IDC header, and I've connected up the reset pins internally to the RED reset button on the back of the case.
Re: Jupiter ACE (again)
Posted: Mon Sep 21, 2020 10:37 pm
by Microsha
Colleagues, I have a question about Jupiter. Built a new Jupiter Ace. Loading from a tape recorder doesn't work. I type Load, and the computer goes into standby mode. I turn on the Wave file from the PC player. After loading, Jupiter is still waiting. I checked the signal with an oscilloscope. On pin 14, Z18, the signal is received. There is also a loading signal on pin 13 of Z18. The speaker also beeps in the same tone as the download. But when there is no download signal, it beeps with a tone of about 1 kHz. What should I pay attention to?
Re: Jupiter ACE (again)
Posted: Sat Sep 26, 2020 5:52 pm
by McKlaud
Hi and congratulation with your build. Regarding the loading issue, try to replace C3 (47nF) to 470nF or more and check.
Re: Jupiter ACE (again)
Posted: Sun Sep 27, 2020 2:41 pm
by Microsha
McKlaud wrote: ↑Sat Sep 26, 2020 5:52 pm
Hi and congratulation with your build. Regarding the loading issue, try to replace C3 (47nF) to 470nF or more and check.
I'm betting more than that. No effect. The signal is available at input 14 Z18
Re: Jupiter ACE (again)
Posted: Sun Sep 27, 2020 3:16 pm
by McKlaud
Do you load TZX files or WAV? Are you sure that your TZX player can generate waveform with correct Jupiter ACE timings and it could be understood by Jupiter ACE? Jupiter ACE timings are different to ZX Spectrum ones.
1kHz sounds right for "0" pulses. Pilot's frequency is approx 800Hz, a logical "1" gives 2kHz pulses.
Please provide more information otherwise we do not know what your are tying to do.
BTW there is a double wave forming and reading audio signal in the Jupiter ACE’a logic. Fist buffer (Z18) convert sine wave into square signal, the second stage buffer (Z14) is controlled by 0xFE port, which is enabled in every 20ms by ROM routines. The same port scans keyboard.
Re: Jupiter ACE (again)
Posted: Sun Sep 27, 2020 5:50 pm
by Microsha
McKlaud wrote: ↑Sun Sep 27, 2020 3:16 pm
Do you load TZX files or WAV? Are you sure that your TZX player can generate waveform with correct Jupiter ACE timings and it could be understood by Jupiter ACE? Jupiter ACE timings are different to ZX Spectrum ones.
1kHz sounds right for "0" pulses. Pilot's frequency is approx 800Hz, a logical "1" gives 2kHz pulses.
Please provide more information otherwise we do not know what your are tying to do.
BTW there is a double wave forming and reading audio signal in the Jupiter ACE’a logic. Fist buffer (Z18) convert sine wave into square signal, the second stage buffer (Z14) is controlled by 0xFE port, which is enabled in every 20ms by ROM routines. The same port scans keyboard.
I take the WAV file from here
http://www.jupiter-ace.co.uk/software_i ... aglistings
The frequency of 1 kHz sounds from the speaker after entering the LOAD command, but when there is no signal from the tape recorder yet. The frequency of the pilot tone is about 800 Hz. The pulse duration after entering the LOAD command on pin 15 Z14 is approximately 17 ms. It is difficult to detect the loading signal on pin 13 of Z14. I'm seeing a mixed signal.
Re: Jupiter ACE (again)
Posted: Sun Sep 27, 2020 6:26 pm
by McKlaud
Pin 13 of Z14 is directly connected to the data line D5 and you can see all data flowing there. Take pin 13 of Z14 out of the socket and then see what you have there during the LOAD execution. If you would like to separate LOAD signal only, the oscilloscope should be triggered by the 0xFE read pulses.
Re: Jupiter ACE (again)
Posted: Sun Sep 27, 2020 8:44 pm
by Microsha
McKlaud wrote: ↑Sun Sep 27, 2020 6:26 pm
Pin 13 of Z14 is directly connected to the data line D5 and you can see all data flowing there. Take pin 13 of Z14 out of the socket and then see what you have there during the LOAD execution. If you would like to separate LOAD signal only, the oscilloscope should be triggered by the 0xFE read pulses.
My oscilloscope is the simplest. Disconnected pin 13 Z14 from the printed conductors. The signal on pin 13 is present. The waveform is modulated by sampling on pin 15. Maybe there is a sample WAV file?
Re: Jupiter ACE (again)
Posted: Mon Sep 28, 2020 7:37 am
by McKlaud
I have never tried to load any WAV files, only TAPs from JAA websites. If you have TZXduino I could share a few files that works and you try with them.
Bear in mind that Jupiter ACE TZX files should be converted to ZX Spectrum timings if you would like to use a bulk standard TZXduino firmware.
Re: Jupiter ACE (again)
Posted: Tue Sep 29, 2020 12:43 pm
by anightin
Hi Folks,
As a follow-on to my Ace backplane extender, I decided that for any useful length of cable that I do need a buffered solution.
Bufferd some control signals, data and address bus.
What are people's thoughts on the attached draft where I've attempted to buffer data and address lines?
Comments welcome
