Spent some time today looking for some info on the J-02 16 pin connector on the back of the P5 radio. I've seen several aux input adapters use this connector, so I was curious as to it's pin-out. Here's what I've found so far (starting from top left to bottom right when looking at the back of the radio):
Pin# Function
1 n/c
2 Speaker RH (-)
3 Speaker LH (-)
4 Text Data
5 n/c
6 Bus (+)
7 n/c
8 B+
9 Power Ground
10 Speaker RH (+)
11 Speaker LH (+)
12 Signal Ground
13 Text CLK
14 Bus (-)
15 Res/Aux Cont
16 ACC
A couple of observations:
The signal lines are differentially driven, meaning each channel has a + and - and a common ground between them. This is commonly used on external audio devices with low-level signals to minimize noise.
The Bus +/- indicate some sort of serial control bus is used. Makes sense if you're trying to control a CD changer, etc. It's not clear if this is bi-directional or not. The protocol is unknown.
Unknowns:
Okay what are the B+ and the Res/Aux Cont pins for? I assume ACC is for Accessory power?
Now, looking at the GROM adapter cable, it appears that pins 6, 8, 9, 10, 11, 12, and 16 are used. Most of those make sense, except for pin 6 (Bus +). If pin 6 is used, I would expect pin 14 (Bus -) to be used as well. Also, the GROM cable is driving the signal lines in a single ended mode just using pins 10, 11, & 12. While this will work, it drops the input voltage by 50% and increases the noise slightly. The fix is to add a pair of differential line drivers. But, they require a split voltage power supply (say +/- 6V). So, a more complicated circuit.
Of course, the pin-out I found might be totally wrong.
I'll keep poking at this as time permits.
Pin# Function
1 n/c
2 Speaker RH (-)
3 Speaker LH (-)
4 Text Data
5 n/c
6 Bus (+)
7 n/c
8 B+
9 Power Ground
10 Speaker RH (+)
11 Speaker LH (+)
12 Signal Ground
13 Text CLK
14 Bus (-)
15 Res/Aux Cont
16 ACC
A couple of observations:
The signal lines are differentially driven, meaning each channel has a + and - and a common ground between them. This is commonly used on external audio devices with low-level signals to minimize noise.
The Bus +/- indicate some sort of serial control bus is used. Makes sense if you're trying to control a CD changer, etc. It's not clear if this is bi-directional or not. The protocol is unknown.
Unknowns:
Okay what are the B+ and the Res/Aux Cont pins for? I assume ACC is for Accessory power?
Now, looking at the GROM adapter cable, it appears that pins 6, 8, 9, 10, 11, 12, and 16 are used. Most of those make sense, except for pin 6 (Bus +). If pin 6 is used, I would expect pin 14 (Bus -) to be used as well. Also, the GROM cable is driving the signal lines in a single ended mode just using pins 10, 11, & 12. While this will work, it drops the input voltage by 50% and increases the noise slightly. The fix is to add a pair of differential line drivers. But, they require a split voltage power supply (say +/- 6V). So, a more complicated circuit.
Of course, the pin-out I found might be totally wrong.
I'll keep poking at this as time permits.
