The Sinclair QL Forum

Popopo wrote: ↑Mon Dec 11, 2023 5:49 pm

stephen_usher wrote: ↑Mon Dec 11, 2023 11:40 am All you need is an ATTiny85 and a way to switch its power on and off using an output from the Pico. In the case of the vDrive I used the activity LED power to switch a transistor. The speaker is directly connected to two of the pins on the ATTiny85.

Hum...
not so simple as I thought.
I think, Noel Llopis did something similar in the place of a LED, need to check it out.
Don't know... how much cost the ATTiny and other components... but remember, I have not vDrive.
So any solution must be independent of 3rd parties solutions

ATTiny85 chips are cheap (£1.50), add a transistor and it's less than £2.

Here's the schematic:


Replace "LED" with an output from the Pico and Bob's your uncle.

Popopo wrote: ↑Tue Dec 05, 2023 11:42 am Side note: FPGA is a hardware emulator since it is not same than original. But... playing words and POVs.

Wikipedia makes a simplified, clear statement: "Emulators are interpreters."
To keep this in mind helps to keep some rationality in using the word "emulator".

Gerbers files,
Of modified version 1.4, use them under your own risk.

https://we.tl/t-c8NcsKyr4X

And schemas attached.
Again, please check circuitery comparing with original version from Dr. Gusman.
I could commit a mistake with my personal documents that I couldn't verify yet.
With schemas, Gerbers and the original Dr. Gusman version, everything could be satisfied for verification.

Cheers.

stephen_usher wrote: ↑Mon Dec 11, 2023 7:02 pm ATTiny85 chips are cheap (£1.50), add a transistor and it's less than £2.

Here's the schematic:


sound-circuit.jpg


Replace "LED" with an output from the Pico and Bob's your uncle.

Humm Uncle Clive spirit, a penny is a penny XD
I will try to check it out, but... perhaps there is another option even cheaper (just the speaker). I will try to get a gap to study it.
Thinking about it... I started to like even more
With last version published (1.4) you have one free line that I kept for compatibility reasons, the red light (activity/status/selected).
So, you could glue your solution in that one. Keep in mind that you should (in that case) consider current and voltage levels (moreover if someone insert a cartridge from previous versions that use this light).
For your use, or own re-design you don't need to keep it in mind. In fact... you can do whatever you want, just warning users (if you bring them your solution) about it (in case it should be considered).

Another option (my prefer one that even I could try it), is to use one GPIO port (analog) to reproduce the sounds Directly to a speaker. So... no need more than one component (the speaker), the footprint and lines on the Board to make it easier for everyone, and to make some modifications on the code. IMHO, that is the most elegant option.

Peter wrote: ↑Mon Dec 11, 2023 10:06 pm

Popopo wrote: ↑Tue Dec 05, 2023 11:42 am Side note: FPGA is a hardware emulator since it is not same than original. But... playing words and POVs.

Wikipedia makes a simplified, clear statement: "Emulators are interpreters."
To keep this in mind helps to keep some rationality in using the word "emulator".

Exactly what many solutions do using FPGAs.
Interpret what it should do since... you have not the original logic schema (technology, context (voltages, etc)) or somebody try to reproduce as close as possible the "real/original" behavior.
POVs of view, if for you FPGAs is same than original, that's fine. Not for me, a scale aircraft is not the same than real Boeing, what also is not the same than Airbus version. Both flights but not with same characteristics, not mention about on scaled one.
Keep this in mind, I hope it helps to don't get confuse the people who is not expert.

Popopo wrote: ↑Mon Dec 11, 2023 11:33 pm Exactly what many solutions do using FPGAs.
Interpret what it should do since... you have not the original logic schema (technology, context (voltages, etc)) or somebody try to reproduce as close as possible the "real/original" behavior.
POVs of view, if for you FPGAs is same than original, that's fine. Not for me, a scale aircraft is not the same than real Boeing, what also is not the same than Airbus version. Both flights but not with same characteristics, not mention about on scaled one.
Keep this in mind, I hope it helps to don't get confuse the people who is not expert.

The word interpreter as it refers to software and the word interpret as it refers to your example of what you think an FPGA does, are not the same. There were Z80 processors made in Russia that were not made from original spec so they "interpreted" how the chip should function, but that is considered real hardware. Point-of-view is a slippery slope here. I think FPGA's fit into the real of hardware, whereas emulators are software...it's a pretty clear delineation. Now you can replace some hardware with software (i.e. PiStorm) but that's just faster software emulating the real hardware.

Popopo wrote: ↑Mon Dec 11, 2023 11:30 pm Another option (my prefer one that even I could try it), is to use one GPIO port (analog) to reproduce the sounds Directly to a speaker. So... no need more than one component (the speaker), the footprint and lines on the Board to make it easier for everyone, and to make some modifications on the code. IMHO, that is the most elegant option.

Well, the sampled Microdrive sound used can be found in the source code: https://github.com/stephen-usher/vDrive ... snd-v1.ino

stephen_usher wrote: ↑Tue Dec 12, 2023 8:01 am Well, the sampled Microdrive sound used can be found in the source code: https://github.com/stephen-usher/vDrive ... snd-v1.ino

I need to implement your solution. I bought the same thing that Noel did and its scraping microdrive sound was pretty bad so I uninstalled it. I really liked your solution.

You don't really need a PCB. My first version was a bit of vero board, a 14 pin socket and some bodge wires.

The Pi Pico probably has enough horsepower to provide that sound directly in response to a request to 'run' the Microdrive motor, and requires only a single pin - connect a resistor to this pin and join it to the resistor that feeds the base of the transistor driving the speaker (I believe this components is close the Microdrives on the QL motherboard)

TR1 is the transistor, R95 is the 1K resistor between +5V and the base of the transistor and this connection comes from Pin 22 of the IPC (large chip near the microdrives)

A similar value resistor connected to this pin from the Pi Pico sound output pin (yet to be determined) could provide sufficient drive to make some sound for you on the QL speaker.