29 Jul
2013
29 Jul
'13
12:09 a.m.
On 7/28/13, Steve Markgraf <steve(a)steve-m.de> wrote:
Yes, and it took me a while. The basic
'on/off' is controlled by the
SPCA with the code we have, the brightness is controlled by the
PWL-unit of the Calypso, but inverted if I remember correctly.
Using your PCB layer pictures, I've traced the PWL signal to the 6-pin
IC near the SPCA. The IC label reads "A3-90E", and considering the
inductor right next to it, I'm guessing that it's a boost converter
for the backlight LED. I'm sure you saw this IC too when you were
figuring the BL out - were you perchance able to figure out the full
name / part # of this IC, or maybe even find a datasheet for it?
At one point I soldered wires to all connections and
hooked them up to
a logic analyzer. It's a 16-bit interface and it was quite easy to
figure out what was what. For all the initialization only 8 bits are
used, for the actual display content you switch to the 16-bit mode.
I thus gather that you had (most of) the actual pinout figured out at
some point. Would you perchance still have it somewhere in your notes?
Kim