Re: ANN: Web Browser for 8 bit Apple //

[david@uow.edu.au (David Wilson)]

>> (3) uIP is ultimately "driven" through a periodic timer.  This timer
>> would basically be an interrupt/IRQ that fires *at least* once a
>> second. (The docs weren't clear on that; the source code for
>> uip_periodic() might reveal more.)  Anyhow, I assume that extra
>> hardware will be required in order to pull it off.  When I owned my
>> Apple //e back in the 80's, I had purchased a card called the
>> "TimeMaster II/HO".  It would generate, if I remember, 24 interrupts a
>> second.  What else can generate timed interrupts?  I'll have to
>> research this, but maybe a mouse card and maybe a super serial card (I
>> don't know how, but I seem to recall reading something to that effect
>> in the last week or so.)

Yes, a mouse card can generate 50/60Hz IRQ.
A //gs can generate 50/60Hz IRQ.
A //c can (I am fairly certain) generate an IRQ at that rate.
A //e ][+ or ][ can not generate timer IRQs without extra hardware
(clock card, mouse card).

It is quite possible to make a very small card with one or two ICs that
could be attached to a //e or ][+/][ motherboard. It could plug into
the 16 pin game socket (this would provide +5v GND, AN2 and PB2 which would
be enough to enable/disable and monitor the status of this device). All you
would need to add is a wire to the IRQ bus on the motherboard.

I did this to my MPF-III //e clone system (although I used an unused latch
on the motherboard and added an open-collector NAND gate to drive the IRQ
line. I also added keyboard IRQ support.

>> 
>> (4) The original //c had serial problems.  I might have that kind of
>>     //c sitting in my office at work.  I found that out here: 
>> 
>>   http://www.intrec.com/proterm-a2/a2_tips_tricks/a2_iic_telecom.txt

An old //c with inaccurate serial timing can be modified to fix this. I have
a m/b modified by Apple - one IC is removed, an oscillator in a can put
in its place and a few traces cut and a few pins jumpered with thin wire.

You cannot tell which //c you have based on the ROM rev as an old board
can have either ROM 255 or ROM 0. You can tell by visually inspecting the m/b
and looking for the silver oscillator tin near the 6551 chips.
 
>> Lastly, I started a web page for Apple // programming; not much there
>> right now, but as time goes on I will add to it.  Tonight I will add a
>> link to a message forum that can be used for talking about
>> programming, uIP and the like.
>> 
>> Here's my URL:  http://www.cosmicwolf.com/AppleII/AppleII.htm

Note that the AppleSoft listing you have is of code copyrighted by
Microsoft and Apple. I hope they do not come knocking on your door.
--
David Wilson  School of IT & CS, Uni of Wollongong, Australia