[Coco] Questions about the Coco3 GIME Timer

[Stephen H. Fischer]

Hi,

I do not know if the 6522 can still be obtained but if they are available
you might save a lot of work.

http://www.zimmers.net/anonftp/pub/cbm/documents/chipdata/6522-VIA.txt

o Two 8-bit bidirectional I/O ports
o Two 16-bit programmable timer/counters
o Serial data port
o TTL compatible
o CMOS compatible peripheral control lines
o Expanded "handshake" capability allows positive control
  data transfers between processor and peripheral devices
o Latched output and input registers
o 1 MHz and 2 Mhz operation
o Single +5V power supply

PORT B (PB0-PB7)

Peripheral   Port   B   consists  of  eight  bi-directional  lines  which
are controlled  by  an  output  register and a data direction register in
much the same  manner  as  the  Port  A.  In  addition,  the polarity of the
PB7 output signal  can  be  controlled  by  one  of  the interval timers
while the second timer  can  be  programmed  to  count  pulses  on  the  PB6
pin. Port B lines represent  one  standard  TTL  load  in  the  input  mode
and  will drive one standard  TTL  load  in  the  output  mode.  In
addition, they are capable of sourcing  1.0  mA  at  1.5  Vdc  in  the
output  mode to allow the outputs to directly  drive  Darlington  transistor
circuits.

Stephen H. Fischer


----- Original Message ----- 
From: <jdaggett at gate.net>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Wednesday, February 14, 2007 1:20 PM
Subject: Re: [Coco] Questions about the Coco3 GIME Timer
>
> No problem. Kind of doing the same here. I am in the process of designing
> a
> CPLD to do PWM to drive servo motors to automate a telescope. I want to
> consolated a few PC Basic programs and modifiy to run on a  COCO1/2/3. I
> will
> have to off load some tasks to dedicated hardware.
>
> james