Pico and i2c

Robert_Kuhn1 · February 3, 2009, 12:36pm

Hello,

I am unable to readout the pico projector via i2c:

root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000
root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0xf0000000
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000

What am I missing?

Robert

Koen_Kooi · February 3, 2009, 12:52pm

You can't do reads, only 'receives' from the pico. There's a comment in the script angstrom ships:

http://cgit.openembedded.net/cgit.cgi?url=openembedded/commit/&id=1813b844deed16544f80399cd880ba5a91562c33

Also, you have your LSB and MSB mixed up, you want to write 0xf0000000 to write a '1' to the pico (see the script).

regards,

Koen

regards,

koen

Robert_Kuhn1 · February 3, 2009, 1:08pm

root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000
root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0xf0000000
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000

What am I missing?

You can't do reads, only 'receives' from the pico. There's a comment in the
script angstrom ships:

Openembedded-Hotels, Villen, Unterkünfte in Leipzig

root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0xf0000000
root@beagleboard:~# bus3-i2c 0x1b wb 0x15 0x08
root@beagleboard:~# bus3-i2c 0x1b vb4
0x00000000
root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001
root@beagleboard:~# bus3-i2c 0x1b wb 0x15 0x08
root@beagleboard:~# bus3-i2c 0x1b vb4
0x00000001

Also, you have your LSB and MSB mixed up, you want to write 0xf0000000 to
write a '1' to the pico (see the script).

???
I wrote 0xf0000000?!?!

Robert

Koen_Kooi · February 3, 2009, 1:29pm

root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000
root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0xf0000000
root@beagleboard:~# bus3-i2c 0x1b rb4 0x08
0x00000000

What am I missing?

You can't do reads, only 'receives' from the pico. There's a comment in the
script angstrom ships:

Openembedded-Hotels, Villen, Unterkünfte in Leipzig

root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0xf0000000
root@beagleboard:~# bus3-i2c 0x1b wb 0x15 0x08
root@beagleboard:~# bus3-i2c 0x1b vb4
0x00000000
root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001
root@beagleboard:~# bus3-i2c 0x1b wb 0x15 0x08
root@beagleboard:~# bus3-i2c 0x1b vb4
0x00000001

Also, you have your LSB and MSB mixed up, you want to write 0xf0000000 to
write a '1' to the pico (see the script).

???
I wrote 0xf0000000?!?!

You did indeed, I got confused by the root@beagleboard:~# bus3-i2c 0x1b wb4 0x08 0x00000001

regards,

Koen