On 7/27/13, Steve Markgraf steve@steve-m.de wrote:
Unfortunately there's only a datasheet of the SPCA554 floating around, just search for "SPCA554AV02".
Found it, thanks.
unfortunately the SPCA552 and 554 seem to have quite a few differences, so not everything could be figured out.
Yeah, the differences do seem big indeed. While I was searching around for an SPCA552E datasheet, I found this:
http://www.download.revosupport.com/scp2009_download_folder!/BONUS%20MEMBER/...
On page 12 of that schematic there's our lovely Sunplus chip. Of course it's a totally different phone, but at least we can see what are the pin interfaces coming off this chip.
In the above schematic, we see that SPCA552E connects to just the host CPU, the LCM and the camera - no frills. But the 554 datasheet you've found describes a much more complex device - adds USB, audio, mass storage...
At least it was enough information to get the bypass mode working, which was my main goal.
Were you ever able to figure out just how the backlight works on this display? Your code has a comment about a particular register in the SPCA supposedly turning the BL on or off, but looking at the pin interfaces of this SPCA in the Nokia schematic, I don't see anything even remotely related to the backlight... Yet the original firmware is able to not only turn this BL on and off at will, but also change the brightness - during calls, the display dims instead of blanking completely.
On a related note, were you ever able to figure out the pinout of the 30-pin flex between the main PCB and the LCM? If this pinout were known, I could probably trace out the stuff of interest to me (like the backlight) on the main PCB using your layer pictures, but if I have to reverse-eng the LCM itself, that might be a bit above my skill level. :(
Since the SPCA has an integrated 8051 core, you probably need to upload proprietary code to get the camera working, or you have to rewrite the firmware for this chip as well...
Bummer. But just out of curiosity, how did you figure out that it's an 8051? Did you see the original phone fw pushing something to the SPCA that looked like 8051 instructions?
FWIW, the 554 datasheet describes its CPU as a "32-bit RISC processor" - too closed to even name what it is!
Kim
Hi,
On 28.07.2013 09:20, ubuntugirl wrote:
Were you ever able to figure out just how the backlight works on this display? Your code has a comment about a particular register in the SPCA supposedly turning the BL on or off, but looking at the pin interfaces of this SPCA in the Nokia schematic, I don't see anything even remotely related to the backlight... Yet the original firmware is able to not only turn this BL on and off at will, but also change the brightness - during calls, the display dims instead of blanking completely.
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. Just play with the bl_level() function a bit.
On a related note, were you ever able to figure out the pinout of the 30-pin flex between the main PCB and the LCM? If this pinout were known, I could probably trace out the stuff of interest to me (like the backlight) on the main PCB using your layer pictures, but if I have to reverse-eng the LCM itself, that might be a bit above my skill level. :(
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.
Bummer. But just out of curiosity, how did you figure out that it's an 8051? Did you see the original phone fw pushing something to the SPCA that looked like 8051 instructions? FWIW, the 554 datasheet describes its CPU as a "32-bit RISC processor"
- too closed to even name what it is!
Now that I see the "32-bit RISC processor"-comment as well... no idea where I got that from, it's most likely wrong then. I didn't look at the instructions, but as far as I remember I've seen a code blob being uploaded.
Regards, Steve
On 7/28/13, Steve Markgraf steve@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
Hi,
On 29.07.2013 00:09, ubuntugirl wrote:
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?
No, and I didn't really care about it to be honest, since it just works.
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?
Unfortunately no, I checked if I still have it on my laptop from 28c3, but it doesn't seem like it...
Regards, Steve
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ubuntugirl