From: Andrew Jamieson <ajamiesn_at_mira.net>
Date: Wed, 12 Dec 2001 18:52:23 +1100

OK. I've done some more connection hunting .... I am working on the
updated schematic at the moment, but for now, here is the most relevant
information:

CS6: This goes to the enable of the 245 latches. I have still not
confirmed that these go to the HD, but I would be _very_ suprised if they do
not. Therefore, CS6 is used for the HD.

CS7: This pops off to disappear under the LCD somewhere: Therefore,
my current guess is that this is used for the LCD enable.

CS2: This is used for the flash ROM.

I2C bus: Both MAS chips do indeed have thier I2C busses connected. The
clock of this goes through a wierd 0R / SOT 23 thingie (its not a transistor
nor a diode - maybe a FET?) and then connects to the TCLKD pin of the SH-1
(PB7 - I'd actually guessed TCLKC on a pencil scribbled schematic just
before starting to buzz the connections out ....). I assume that the data
is sent over PB5 (which pops through the inter PCB connector just next to
the TCLK signal), but it also seems to go through a wierd circuit (that I
haven't found yet) that is screwing with my continuity check. I'm 98%
certain that this is the I2C data line tho. Bottom line: There is an I2C
connection to both MAS chips, using PB7 as the clock line, and probably PB5
as the data line.

Remote: The remote uses RxD1 (PB10) to connect to the 2nd ring on the
earphone socket. TxD1 goes to a pad on a non-loaded component - maybe they
were thinking of having data ouput earphone socket and never implemented it
properly, or it was too expensive. They may still be muxing TXD on the
earphones through a diode resistor thingie I haven't found yet, so don't
give up hope yet. I will check for signals coming out of this line soon
....

Music input to MAS 3507: Music data is sent to the MAS 3507 via serial
port 0, with TxD, RxD, and CLK signal doing the obvious stuff.

That's all the interesting stuff. I will update the schematic and send it
out for those that are interested by this sort of stuff.

Have fun ppl ;)


CM
Received on 2001-12-12