8 Mar
2005
8 Mar
'05
1:55 p.m.
On Tue, 2005-03-08 at 15:41 +0000, Jules Richardson wrote:
Yup. Mouse is getting power. One of the first things I verified.
On Tue, 2005-03-08 at 09:21 -0500, David Holland
wrote:
I built this thing:
http://www.bobblick.com/techref/projects/picprog/picprog.html
Component cost is pretty low, and the propic2 software off that page
(while Windows based) programs the 16F628's well enough.
(Verify doesn't work however. - Just read the device, and eyeball it.)
Hi,
Has anyone successfully built one of the PS/2 -> Indigo adapters off of
the following page?
No, but I've seen that page before - lack of a PIC programmer has
stopped me building one (or two). We've got a 4D/25 and two Indigos, but
only one SGI keyboard between the three... When I hook my scope up to the clock and/or data
PS/2 lines, I see no
data being received from the mouse.
Obvious one: have you checked that the mouse is getting power?
I don't actually know whether the PIC is supposed to generate the mouse
clock or whether the mouse does though... if the former then you'd
presumably see something on the clock line if the PIC was running.
According to the data I found on the PS/2 spec, it depends. If the
mouse is talking, it twiddles the clock line. If the "host" is talking,
it twiddles the clock line.
I _think_ I see a little initialization data pass down the line, to the
mouse, when I first power up the device, but my o'scope isn't a memory
type, so it might just be power up noise.
Hence my suspicion that it might be a initialization issue.
Looking at the schematic, how the heck do PICs reset at power-on?
Internal reset @ power-on circuitry.
You also need to tie ~MCLR to VDD via a resistor.
(Which is an error in the schematic. - And my PIC's wouldn't "run" till
I did so.)
I used a couple of 4.7K, as it was what I had lying around.
Presumably it's internal - I'm suprised reset
isn't under user control
on one of the pins though...
If I understand the datasheet, its a function of ~MCLR, and the config
bits, and if you were to drop it to ground, it'd reset the device.
cheers
Jules