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| From: Richard Atkinson
Date: 2001-03-22
Subject: V364 words and asic pinout
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It's been a while since I posted to either list, but I have some news which may be of interest to many of you. For the past month and a half I have been in Austin, Texas working for a tech company and I took the opportunity to visit Bo Zimmerman.
Bo and I worked on his V364 among other things and we took some recordings of the speech chip words. The results are at www.zimmers.net on his V364
page. Whereas the Magic Voice has 235 words, the V364 has 261 words and a modified version of Daniel Spiteri's Magic Voice word list is available on Bo's site. The V364 has the same words as the Magic Voice (with the exception of 3 less duplications) and some extra words at the end, mainly BASIC 3.5 function names. Some of them were nearly unintelligible, so we were fortunate that the BASIC 'SAY "WORD"' construct also works. In this way we were able to determine all of the uncertain words. Listen to 'go'
and 'hide', for example. Finally, 'grey' is replaced by 'pink' as the word grey is not used in the 264 series colour palette (being a shade of white)
whereas pink is.
The ROM has been on Funet for some time, thanks to Bo's efforts when he first obtained the machine. It ought to be possible to get the Magic Voice to say the extra words, using excerpts from the V364 speech ROM. The V364
speech hardware uses the same Toshiba PARCOR speech synth chip (T6721A,
datasheet on Funet) but a more integrated arrangement of glue hardware. The speech ROM is in a socket to the left of the BASIC ROM and it occupies slot 3 LOW in the ROM banking scheme. The empty socket to the left of that is for slot 3 HIGH. There is a single custom ASIC for the glue logic to the left of that, so the complete listing of V364 28 pin chips from left to right in the line goes 8706R0 (custom ASIC), empty
(slot 3 HIGH), speech ROM (slot 3 LOW), BASIC ROM (slot 0 LOW), KERNAL ROM
(slot 0 HIGH), 3 PLUS 1 ROM (slot 1 LOW), 3 PLUS 1 ROM (slot 1 HIGH), PLA.
This ASIC replaces the 6525 TIA, 40105 fifo and gate array inside the Magic Voice. It has four registers and banks in at $FD2x, which is the unused PLA decoded address range (function 0) on all other 264 series machines. There are probably four mirrors of the ASIC registers; we did not check for this functionality at the time. I took the opportunity to obtain this ASIC's pinout, as a first step towards reverse-engineering the hardware and maybe one day making a speech attachment for a plus/4 out of a modified Magic Voice. Here are the results of the investigation:
U27 8706R0 (1284) Custom speech glue logic ASIC
1 RESET# (cpu) 28 +5V
2 IRQ# (cpu) 27 D0 (cpu)
3 R/W# (cpu) 26 D0 (t6721a)
4 phi 0 (cpu) 25 D1 (cpu)
5 $FD2x# (cpu) 24 D1 (t6721a)
6 A0 (cpu) 23 D2 (cpu)
7 A1 (cpu) 22 D2 (t6721a)
8 ? ? 21 D3 (cpu)
9 EOS# (t6721a) 20 D3 (t6721a)
10 APD (t6721a) 19 D4 (cpu)
11 phi 2 (t6721a) 18 D5 (cpu)
12 DI (t6721a) 17 D6 (cpu)
13 DTRD (t6721a) 16 D7 (cpu)
14 GND 15 WR# (t6721)
There was one pin which did not seem to be connected to anything else on the V364 motherboard; pin 8. Whether this pin is NC internally or an unused function I am not sure; multimeter testing of this pin on the working V364 showed it constantly at 0V, but I cannot say for sure there was no signal on it. In any case, any function it might have would be of academic interest. The next phase of V364 hardware investigation will involve oscilloscope and (hopefully) logic analyser testing, but this could be a long time in the future.
The next part of the overall project will start to determine what function the bits of the 4 registers have; and hopefully come up with a way to attach a Magic Voice (or parts of a Magic Voice) to another 264 series machine in a V364 software-compatible way. This may be of interest to emulator authors. Has anyone tried the V364 ROM in an emulator recently?
Richard
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