digital storage device to replace tape recorder?

[newTIboyRob]

All good points to consider, thanks.

[Artoj]

Hi newTIboyRob and fellow TIers,

 

After reading some of the posts regarding the inconvenience and unreliable nature of the Cassette player for storing programs and data, I decided to have a go at designing a digital tape player. I looked around and found the aPR33A3 28 pin chip was the best choice, I soon realised that it could plug directly into the back of the TI99/4A without too many issues. (this is only a prototype design)

 

(ref pic) The 8 buttons on the left are the memory storage locations, the slider switch is for play and record and the last button is to stop all operations and go to standby. I did not include a battery as the data is not lost  when the power is turned off.

 

I have included a few extra jumpers in case you want to control the device from assembly using the CRU.

SBZ 22    =    record
SBO 22    =     play

SBZ 23    =    start     Memory 1
SBO 23    =    stop    Memory 1    

 

The resistor R3 in the PDF sets it at 47K which gives you 341 seconds (5.683 min) with a sampling frequency of 12khz. This can be changed, here is the chart:

Resistance    Freq     Sec         Min    

189k           6k         682        11.36
147k           7k         584
115k           8k         512
95k             9k         454
76k            10k        408
60k            11k        372
47k            12k        341        5.683

 

The TI Cassette signals uses:

689.37 hz     = 0
1379 hz     = 1 

 

The 3D picture shows the DB9 Port on the wrong side of the PCB.

 

I have not completed this work as yet, I will be adding other options and further investigations in the future on my Mini PEB thread, Regards Arto  

[newTIboyRob]

Wow Arto, it certainly would be some kind of achievement if you could in fact pull this off!   It would also bring peace of mind, certainly to me. Even more of a bonus if you could build it up all ready to go for those of us, like me, who aren't exactly tinkerers!   By all means, please keep us posted on your progress with this!

 

[+khanivore]

@Artoj sounds really cool.  12kHz should be plenty since its like 5 times the nyquist minimum but 6khz might be getting a bit tight for timing.  The ROM just measures the time between zero-crossings when reading.  But still 5 minute should be enough to store a 12KB program.

If you want to achieve really high density you could convert to binary by sensing the zero crossings during recording and then playing through a switchable oscillator when playing at 689 baud 🙂

 

(Actually just realised its 1379 baud, 2 bits per cycle at 689Hz, so 5 minutes definitely more than enough)

Edited October 29 by khanivore
Clarification

[globeron]

On 10/25/2023 at 3:46 PM, newTIboyRob said:

Let me think here a minute. If my PC is upstairs and my actual TI is downstairs, you are saying I could record a WAV file to my PC up here using a USB sound card? (My PC has its own sound card)  Now I would go back downstairs to my TI. I could then get that WAV file from PC back into TI the without an actual tape?  I don't quite follow, could you explain a little please?

 

I think I tried something similar to what you said on page 3 of my other post, the one you asked me about yesterday called "I/O error 66=?"   

 

See the PDF for the setup - (I have a drawing here, I used PC speakers in between and used that 3.5mm plug via the TI-99/4a Cassette cable to the Cassette port of TI-99/4A)

 

 

Here is an example, loading .wav files from a PC to a TI-99/4A   

 

 

 

Edited October 29 by globeron

[HOME AUTOMATION]

The inspirations for this were more along the lines of a voice prompt system to work with or replace the speech synthesis.
But, should be good for CS1, as well. It's nice that you can enter track #s directly from the remote control.
I don't have one setup right now. I recall testing with 4 or 5 digit, track entries.

 

 

[newTIboyRob]

@globeron.. hello, so I see that your video above was using the PC and WAV files to load and run some of those games. What I was looking here though was a device to record and playback from, similar to what @Artoj has been designing or a device  @HOME AUTOMATION was discussing with us, or best of all the NanoPeb. Though I'm aware that the TI software library is really cool, believe it or not, I really wouldn't need more than the actual one last cartridge I am searching for, which is Extended basic. (There is actually even one more I would love, but has been even harder to track down, called TI-Calc as mentioned about 5 years ago in a thread that @Ksarul described nicely: the actual cartridge, (not the Ti-99 4/a Calc extended basic program heretofore explored which I found terribly lacking.)

 

So the upshot is that once I do have those remaining 2 cart/s, I could use those and also use the Extended Basic to write programs more in depth with the speech synth and record and playback with either a) NanoPeb I may still obtain from someone on the forum or b) Arto's device, if and when it's ready and available here in the states or c) getting that specific Made In China Olympus digital recorder mentioned throughout the thread. If I get lucky, one of those 3 solutions will pan out, especially the NanoPeb.

 

In short, if I can avoid using the PC here I would like to, not only due to the logistics in my home, but for my actual need of specific use I originally outlined: to have a reliable, but digital version of a device to replace the Ti 99 4/a's tape recorder for worry-free program saving and loading on the TI after Ti Basic programming or for saving data files from carts like my Console Writer and hopefully this Ti-Calc cart, which would be the cherry on top.

 

Edited October 31 by newTIboyRob

[globeron]

 

@newTIboyRob  with the nanopeb you do not need the digital tape recorder correct?      You use the  OLD DSK1.    or OLD DSK2.     and SAVE DSK1.    etc.

The Nanopeb can have 3 Disks active at the time.    (and change with CALL MOUNT(1,1)  CALL MOUNT(1,3), etc. 

 

 

 

 

[newTIboyRob]

@globeron ... I am trying for either the Nanopeb or the even more outdated CF7+card or someone who could build me either one, in which case, you are correct I wouldn't need the digital tape recorder. I am just trying to see if the NanoPeb can work out first, as it contains the 32K RAM expansion plus the disk drive concept which would allow me to run a cartridge that require those instead of just the digital tape recorder that wouldn't accomodate this by itself.  So... still on hold here with the entire situation!

Edited November 3 by newTIboyRob

[RickyDean]

On 11/3/2023 at 12:56 AM, newTIboyRob said:

@globeron ... I am trying for either the Nanopeb or the even more outdated CF7+card or someone who could build me either one, in which case, you are correct I wouldn't need the digital tape recorder. I am just trying to see if the NanoPeb can work out first, as it contains the 32K RAM expansion plus the disk drive concept which would allow me to run a cartridge that require those instead of just the digital tape recorder that wouldn't accomodate this by itself.  So... still on hold here with the entire situation!

The website for the NanoPeb/CF7 has ben gone for a few months, but can still be accessed on https://web.archive.org/web/20230325044616/https://nanopeb.com/

You may scroll to the bottom and email the address there to see if the person who built these may still have some stock.

[newTIboyRob]

Thank you @RickyDean ... very helpful. I didn't even know that the virtual diskettes were called "volumes" as I had been wondering about that.