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Re: I have a IIgs. So now what?
Michael J. Mahon wrote:
> Tristan Mumford wrote:
>> Jon wrote:
>>
>>
>>>On Mar 2, 8:50 pm, "David Wilson" <mcs6...@gmail.com> wrote:
>>>
>>>>But I just had a look at the circuit diagram for theDisk ][ controller
>>>>card (in The DOS Manual) and it uses the 74LS05 (the low voltage
>>>>version of the 74LS06). Jaycar do sell these:
>>>>
>>>>CAT. NO. ZS5005 RRP $0.60
>>>
>>>Hmm, even more interesting is, Jaycar also has 7406s (CAT. NO.
>>>ZS5806). Is the clone Disk ][ controller a 1:1 clone of the apple
>>>card? It might be better then to use the 74LS05?
>>
>>
>> No, it's rather different. it only has one big rom, which is 2k in size
>> and paged. To be honest I like it better than the real thing.
>
> Tristan, if you want to be *sure* that the '05 is an appropriate
> IC, check the output pins on the empty socket that the '06 was in
> while the controller is powered and see if any of them is pulled
> up to a voltage higher than +5v.
That's a point. I was only referring to the controller and not the IC in the
previous post though. I guess I should have explained myself a little
better.
But yes you make a valid point. I'll have to check out the pins for voltage.
I can't see anything going above +5v considering all the signals seem to be
0v - 5v, or as close as TTL allows anyway, but there may be higher voltages
there.
One thing's for sure, that little chip is getting it's very own socket.
Tristan.
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