Hi Craig,

I got JTAG working (thanks to #osmocom!). I first recommend you get a C115 or C118 with JTAG exposed, which is much easier than having to remove the shields. However remove the plastic cover which makes soldering GND, TDI, TMS, TDO & TCK easier - be careful not to short them the surrounding shields! You will see there is actually 8+9 pads, you must disregard the pin that is left of CTS (it is not shown on http://bb.osmocom.org/trac/raw-attachment/wiki/MotorolaC123/compal_testpads.png). Finally you need a proper VREF. As for me, I just connected the internal 3.3V (TP4) on my Flyswatter2 to the VREF, it appears to work fine (the Flyswatter1 has a jumper that you can use to bridge VREF and 3.3V).


On Fri, Oct 4, 2013 at 5:08 PM, Craig Comstock <craig_comstock@yahoo.com> wrote:
I cracked open the shield on my C139 and didn't see the TPs I expected from the schematic. I thought maybe the angle of the photo on osmocom hid the TPs but it really didn't.

I'll try my C115 instead since that is more clear and accessible. Flashing hello_world on my C115 seemed to fail in a similar fashion as it does on my C139 so maybe the same issue exists there.

I was wrong too... it was TP16 not TP6, so I found TP16 but still haven't located TP8 on the C139 schematic.

-Craig


From: Craig Comstock <craig_comstock@yahoo.com>
To: "baseband-devel@lists.osmocom.org" <baseband-devel@lists.osmocom.org>
Sent: Thursday, October 3, 2013 9:57 AM
Subject: c139/c140 jtag anyone?

I'm at the point w/ flashing firmware where I feel like I need to use a debugger w/ JTAG. I figured I could probably use serial line logging somehow but JTAG seems better and I should learn it anyway.

Has anyone pried open the shield on a c139/c140 and tried attaching to the JTAG test points that are just inside the shield next to the test points which are accessible via the battery compartment?

From what I can gather from the schematics:
TDI - TP8
TCK - TP17
TDO - TP16

TMS - TP18

Looking at the board from the battery compartment side with the top of the phone pointing North/Up I see at least TP17 is near the right-hand bank of test points visible from the battery compartment. From left-to-right there I see something like: TP12, TP18?, TP16?, TP17 so it looks like I have two of the TPs I need: 17 and 18.

I can't seem to find TP6 or TP8 anywhere on the schematic.

-Craig