TheBackShed.com

Forum Index : Microcontroller and PC projects : DECtalkMini for Raspberry Pi Pico

Author

Message

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 08:21pm 03 Dec 2025

Copy link to clipboard

Print this post

Hello everyone,

Does anyone know DECtalkMini?
https://github.com/dectalk/DECtalkMini/tree/dectalk-develop
That's a really good-sounding voice output.

Here you will find a ready-made UF2 file with 9600bps via GPIO 0/1 and audio OUT on GPIO28. I haven't tried it yet, only the version for the Nintendo GBA, but it sounded pretty good!
https://forum.classic-computing.de/forum/index.php?thread/31185-dectalk/&postID=584586#post584586

Frank

ville56
Guru

Joined: 08/06/2022
Location: Austria
Posts: 382

Posted: 11:56am 04 Dec 2025

Copy link to clipboard

Print this post

Back in the late 1980ies I thought of introducing the device in the manufacturing shopfloor I was responsible for as IT manager. The problem was that it did not speak german and the price was rather high (as all the DEC stuff we used) and so I abondoned the idea sooner or later. Had some demos at the local sales rep and was quite impressed but not suited for our usecases. And yes, it was nerdy at that time, so I liked it. But a handful of VT320 terminals did the job as well to deliver the information .... Interesting to see this is still in the minds of others.

Gerald

73 de OE1HGA, Gerald

bigfix
Senior Member

Joined: 20/02/2014
Location: Austria
Posts: 130

Posted: 12:27pm 04 Dec 2025

Copy link to clipboard

Print this post

Toys...

THIS is a real Dectalk from the 80s

I did not power it on the last 30 years...
Need to check the PSU first

cheers
Guenter (with tons of real DEC HW - and no time to play...)

ville56
Guru

Joined: 08/06/2022
Location: Austria
Posts: 382

Posted: 01:15pm 04 Dec 2025

Copy link to clipboard

Print this post

All DEC hw I still have is part of a VAX11/750 cpu chipset and a 16K words Unibus core memory from a PDP11/34. The core is really impressive when looked at through a microscope.

73 de OE1HGA, Gerald

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 08:36pm 04 Dec 2025

Copy link to clipboard

Print this post

Here you can try out the DECtalkMini:

https://bytesizedfox.dev/

Frank

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 06:05pm 10 Dec 2025

Copy link to clipboard

Print this post

Last weekend, I set up an DECtalkMini with an Raspberry Pi Pico. I can really recommend it! It supports multiple voices, different speeds, and has a very good sound. It's the perfect thing for giving a µC a voice.

Frank

cosmic frog
Guru

Joined: 09/02/2012
Location: United Kingdom
Posts: 307

Posted: 09:58pm 11 Dec 2025

Copy link to clipboard

Print this post

Frank N. Furter said Last weekend, I set up an DECtalkMini with an Raspberry Pi Pico. I can really recommend it! It supports multiple voices, different speeds, and has a very good sound. It's the perfect thing for giving a µC a voice.

Frank

Hi Frank, I tried the link but it will not allow me to download. Just says - "Access denied. You’re not authorized to view this page."

Dave.

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 07:56am 12 Dec 2025

Copy link to clipboard

Print this post

Oh, I forgot that you now have to be registered on the forum to download anything.
I've attached it here...

dectalk_mini_pico.zip

...and her a version for USB and GPIO:

DECtalk_Muni_dual_USB_serial_FIFO.zip

GPIO0: UART0 TX
GPIO1: UART0 RX
GPIO28: audio out (PWM)
baudrate: 9600,8,N,1

I tried the DUAL version, but only via USB. A filter like the one on our boards would be advisable. One of my active speakers sounded awful, but another (without modification and without any filter) sounded perfect!

Frank
Edited 2025-12-12 18:13 by Frank N. Furter

cosmic frog
Guru

Joined: 09/02/2012
Location: United Kingdom
Posts: 307

Posted: 06:09pm 12 Dec 2025

Copy link to clipboard

Print this post

Thanks Frank.

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 07:18pm 13 Dec 2025

Copy link to clipboard

Print this post

There is now a new version for PWM and I2S:
DECtalk_Mini_Pico_Dual_I2S_PWM_13122025.zip

https://github.com/dectalk/DECtalkMini

Frank

mclout999

Guru

Joined: 05/07/2020
Location: United States
Posts: 499

Posted: 10:41pm 13 Dec 2025

Copy link to clipboard

Print this post

If you know how to use the Phonemes System of the SAM-based Text to speech in. MMbasic, you can get Similarly Good output. SAM curent page.
I can't seem to find the original manual listing for SAM. It was very helpful. I may have it in my Archives somewhere.
Edited 2025-12-14 08:52 by mclout999

They call me Shai-Hulud (The maker)

Frank N. Furter
Guru

Joined: 28/05/2012
Location: Germany
Posts: 1038

Posted: 08:19am 14 Dec 2025

Copy link to clipboard

Print this post

@mclout999:

Are you familiar with our S.A.M text-to-speech chip?

https://www.thebackshed.com/forum/ViewTopic.php?TID=8202&P=8#127861

Frank

mclout999

Guru

Joined: 05/07/2020
Location: United States
Posts: 499

Posted: 11:00am 19 Dec 2025

Copy link to clipboard

Print this post

Frank N. Furter said @mclout999:

Are you familiar with our S.A.M text-to-speech chip?

https://www.thebackshed.com/forum/ViewTopic.php?TID=8202&P=8#127861

Frank

No I never saw that Thread. I will look at it closer when I can. Thanks.

They call me Shai-Hulud (The maker)

Print this page

To reply to this topic, you need to log in.