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I am not sure if it will be of interest here, but I found some pictures of my first computer controlled Dalek build in 1982.

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OMG, did I once look that young!

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The Dalek was controlled via an RF link with a modified ZX81 computer (you can see the battery backed RAM that held the robots program and data when powered off). It also had very crude speech recognition (you can see the microphone/ultrasonic person detector above the keyboard). I designed a speech recognition algorithm that worked by detecting the zero crossings on the speech waveform, it worked well with command phrases.

This Dalek much later on also worked with a pocket RF transmitter (keyfob size) where I could follow the Dalek and control its movement with my hand in my pocket pressing the fob buttons so no one observing could see this and it looked like it was intelligently moving by itself. When I was product designer for one of the Worlds biggest car alarm companies, we used this Dalek (and RF fob) to hand of brochures at shows/conventions, it was always a hit strolling down the aisle threatening everyone that did not take a brochure!

Tony
Toymaker
Commented February 2015
LOL Rich, I am a fat guy now eating too many burgers! What I meant about interest is that the robot is a bit of a relic now, as the tech is so out of date so it may be boring for some folks.

Richard R, Sinclair basic was so painfully slow that we had to use machine code (as it was referred to in those days where we had to POKE instructions/data registers etc into certain memory locations in a block of fixed memory) to do anything serious. In these early days (gosh I sound like Grandpa Simson!) we had to place this machine code in a large REM statement at the start of the program and a 16K Byte program would take over 20 minutes to save/load from a cassette recorder!

Tony
Toymaker
Commented February 2015
Here is how the Black Dalek looked in 1984 with some silver paint and a movie Dalek type claw. He is with my mini-me Dalek who was also controllable by the modded ZX81 computer.

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Tony
Herr Ball
Commented February 2015
I still have a TS1000 with the extra 16k memory module.
16K ... lol
DJ Sures
Commented February 2015
I commented on facebook - but this is such a cool story. I'm intrigued by the computer. The rom battery backup - the program. machine code. all of it! I love oldschool tech.
Toymaker
Commented February 2015
DJ, Its great that you like the old computers! I have most of the first ones still in my loft somewhere.

The first Sinclair computer was the ZX80 (1980) which had a Z80A, 4K ROM and from memory around 17 TTL chips. This was the first computer to be sold for under £100. It was such a big success that a second Sinclair computer was bought out in 1981, the ZX81 - this had 8K of ROM and now only 4 chips, which were the Z80A, 8K ROM, 1K RAM and a ULA (uncommitted logic array) the ULA did away with the 17 TTL (logic glue) chips. This 4 chip (very small for the time computer) made an excellent robot controller and sold for under £50.

The Z80A microprocessor has a 8 bit DATA bus and a 16 bit ADDRESS bus (that could address 65536 bytes) on theses devices ROM and RAM are mapped in the same address space (also I/O is address mapped in the same space).

The first 8K of the address map was the ROM, then there was a "ghost" 8K - computer programs started at address 16514 (not 16384 as would be expected). I found it was possible to hold programs in the ghost 8K space, so I placed a low (data holding) current 8K RAM chip in that address space, this had a rechargeable battery sitting on top of it (that can be seen in the close up photo) and this was part of the systems non-volatile memory. The other (lower PCB) shown on the right was an address mapped 3 x 8 I/O port (for sensors and controlling stuff) then the other 40pin chip was a phonetic speech synthesiser (General Instruments SP0256) which fortunately already sounded like a Dalek! and that was Commander's (that was the Daleks name) voice. As it was phoneme (allophone) based it could be programmed to say anything. The speech was transmitted by RF to the Dalek which had an internal speaker.

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The Sinclair ZX81 was sold in the States as the Timex 1000.

Here are some links:

The Z80 microprocessor

The Sinclair ZX81

The SP0256 Allophone speech synthesiser

Tony
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Avatarby Toymaker
Published Wednesday, February 18, 2015