[sdiy] SN76477 & SN94624/TMS9919

[anthony]

> packaging, for under $10 I think:

That's pretty good.

>
>         http://www.analogue.org/mr/sas/sn76477n_1_liten.jpg
>         http://www.analogue.org/mr/sas/sn76477n_2_liten.jpg
>
> Were they often packaged & sold by Radio Shack?

I don't recall RS having them. I started messing with electronics in the 
early 80's and I only ever remember seeing these in the back of Radio 
Electronics in the Jameco ads and such.

I /did/ get an SAD4096 (or whatever that bbd they had was), an SE570 (I 
think it was a '70 but maybe it was a '71?) and a speech synthesizer chip 
when they went on clearance. I have no idea where these parts have got to. 
The bbd was rad.

>>I have a SN94624/TMS9919
>
> What's that?

It's the sound chip from a Texas Instruments TI-99.

It's pretty small and simple and you really need to hook it up to a computer 
to use it effectively, but after looking at a makeshift datasheet that 
someone posted on the web, I think with some TTL or CMOS chips here and 
there you can easilly use it for sound effects at the very least. I do have 
all the numbers to make it musical though. I thought I might hardware some 
sequences on it. I also thought of a sort of keypad that would put bits in a 
buffer that you could dump manually. It /is/ a single chip solution for a 
tunable noise source too.

I've also been thikning of noisy things to do with all of the Mostek DTMF 
chips I have. But thaat's just simple screwing around with the clock speed.