[DECtalk] DecTalk emulator

[Don]

On 7/29/2019 12:19 AM, Aksel Leo Christoffersen wrote:
> The zip-file from archive.org, is the exact same emulator, just without
> MAME. I’ve tried it my self.

MAME is the emulator:  Multiple Arcade Machine Emulator.

To emulate different arcade games, it -- as a program -- PRETENDS to be
various types of computers.  When "fed" EXACT COPIES of the Read Only
Memory chips that were installed in those games, the corresponding
CPU chip emulator interprets the contents of those ROMs to behave in a
manner similar to the actual, physical CPU chip did in the real game.

Because the original CPU chips used in these arcade games were so much
slower than modern CPUs in our PCs, the emulator PROGRAM can provide
comparable performance in a PC even though it has to do far more work
to interpret what the ROMs would have told the original CPU chip
hardware to do.

The original DECtalk product was implemented with a Motorola MC68000
microprocessor accompanied by sixteen 16KB ROMs -- 256KB of "program".
This included all of the algorithms to convert the text that was
presented to the TTS via its serial port.  They also contained the
various letter-to-sound rules used to convert arbitrary sequences of
characters (words) into sounds.  As well as rules to handle words
that were "exceptions", rules to convert sequences of digits into
spoken numerical quantities, etc.

A Texas Instruments TMS32010 Digital Signal Processor (a very fast
CPU optimized for doing the sort of math involved to create waveforms)
generated the actual audio signals that were fed to the speaker.

(They could also be fed to a telephone line due to the design of
the hardware -- your DECtalk could answer the phone and interact
with the caller using synthetic speech).

The ZIP file mentioned is just the contents of the ROMs -- two different
versions.  The "suffix" on each file determines which physical ROM chip
gets the contents of that file.  So, "e18" is an actual chip designation
on the circuit board.  Noting the presence of two e18's means there are
two different versions of the contents for the e18 ROM chip.  Ditto with
the other ROMs.