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DECTalk on a MicroVAX 3100

marmotking

Experienced Member
Joined
Feb 2, 2007
Messages
179
Location
Seattle, WA
I have a working DECtalk DTC01. What a beauty! However, I don't know how to properly hook it to my MicroVAX 3100. The port I plug it into comes through as device TTA0: in VMS. And, no, that's not the console port due to the position of the break enable switch on the machine. But that's a 3100 detail. So, if the DECtalk is simply connected to the TTA0 port and switched on, it's clear it's getting the VMS login prompt, because it tries to speak it. Is there some way I should be telling VMS that there's not a terminal on that port and not to attempt to log in a user on that port? Is this necessary for the DECtalk? For those of you familiar with the MicroVAX 3100, TTA0 is the first of the three MMJ plugs on the back. It's labeled "1" on the actual machine box.
 
DECtalk Manuals here

The first thing that occurs to me is to ask if the DCT01 was plugged in and turned on when the VMS system was started?

From what I'm seeing VMS may recognize this device and set many terminal parameters itself upon startup.
 
DECtalk host parameters

DECtalk host parameters

So, I've looked through the manuals linked in the last reply (thanks very much, btw) and did some fiddling. The DECtalk allows you to plug it into a terminal and into a host computer. It has two serial connectors for these purposes. If you have both connected, the DECtalk passes the communications through between the host and the terminal, and speaks everything that goes between them. Very neat, actually. You can change this behavior via the DECtalk setup prompt. To get to the setup prompt, send a break signal from the terminal connected to the DECtalk. This gives you the SETUP> prompt. From there you can use "help" to see what to do. In this case, "set host speak off" turns off the speaking of the communications between the terminal and host.

So, what I was initially trying to do is program the DECtalk using VMS Pascal. While the DECtalk seemed to be speaking the "terminal to host" communications fine, it was saying gibberish or nothing when accessed programmatically. It turns out there's a separate baud rate setting for host communications to the DECtalk. Using "show host" from the SETUP> prompt, I saw that the speed was set to 1200. So, I set it to 9600 from the "SETUP>" prompt and now the following VAX Pascal program works:

Code:
[inherit ('sys$library:pascal$dtk_routines.pen')]

program test (output);

var
    voice_id : unsigned;
    device_type : integer := 1;

begin
    dtk$initialize (voice_id, 'TTA0:', device_type);
    dtk$speak_text (voice_id, 'Hello world!  You have been eaten by a gru!');
    dtk$terminate (voice_id);
end.

In case anyone cares... :)

Be safe out there everyone!
 
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Or if you like VAX assembly (which I love)

Or if you like VAX assembly (which I love)

Code:
        .TITLE          DECtalkTest

port:   .ASCID          "TTA0:"
voice:  .WORD
device: .WORD           1
msg:    .ASCID          "You have been eaten by a gru!"

        .ENTRY          main, 0

        PUSHAW          device
        PUSHAW          port
        PUSHAW          voice
        CALLS           #3, g^dtk$initialize

        PUSHAW          msg
        PUSHAW          voice
        CALLS           #2, g^dtk$speak_text

        PUSHAW          voice
        CALLS           #1, g^dtk$terminate

        $EXIT_S
        .END            main
 
DECTalk for Visuallly Impaired?

DECTalk for Visuallly Impaired?

Was DECTalk for the visually impaired as I assume from the user manual or were there other applications?
 
It had a lot of uses. The DECtalk is most famously used by Stephen Hawking as his voice. It also has phone connections and phone control features so that you could use it for automated calling or phone menus, etc. The one I have is from 1984.
 
How does one tell the vintage of one's DecTalk? I see no dates on mine.

I recall it in use in 1984, so I know it dates at least that far back. Looking at it again for the first time in years, I am reminded how nice DEC hardware was.

Makes me a bit melancholy.
 
If you sign into the SETUP> prompt, there's a command for doing a self test. I found it using the SETUP>'s help facility. I can't remember what the command is, but it will speak all sorts of things about the unit, including the date of the ROMs and other things. I think the command is "test speak".
 
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Neat! I've been looking for a DTC01 for a while now. These things can't be very common. Only a few mentions on the web and until now I've only heard you two guys mention you have one.

A youtube clip with speech would be very much appreciated :D
 
No, they're scarce as hen's teeth. [maybe worse]

There were follow-on products [DCT02, 03...] which I've never seen. The 01 is a "Standalone" product, while at least one of the others is apparently a Board Level [QBUS?] version. If I'm not mistaken, there's a software implementation in the MAC [for OS8?]

I need to check mine to see which firmware it has. No DecTalk firmwares in Pete's list.
 
As I suspected. Finding a q-bus version would be fun. I've seen versions for PCI and modules for what looks to be a rather odd rack mounted thing probably meant for telecom equipment racks. And the version Stephen Hawikings used before is standalone and smaller than the DTC01.
 
My DECtalk at Seattle Retro Computer Society Saturday

My DECtalk at Seattle Retro Computer Society Saturday

I'm bringing my VAXcluster, DTC01 and a DECserver 200/MC with a VT100 to the monthly Seattle Retro Computer Society meeting if anyone's in Seattle and interested to see any of it.

For those who don't know what that is, we're a group of people meeting monthly at the Living Computer Museum (open to the public by appointment only). More visitors are always welcome to our meetings! Here are the relevant links:

http://www.seattleretrocomputing.com
http://www.pdpplanet.com

There is an extensive collection of DEC equipment there that's restored and running which you can tour while at the meeting. Mostly people bring pieces of their collection to either show off or get help with from other members.
 
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