CDM1250 accessory connector programming

[cwolf520]

Hi all,

I am working on a cdm1250 and want to change frequencies using the accessory connector and a timer/counter circuit, put an identifier on the current frequency and then go onto the next frequency. I think I have every thing working right. I am using a 555 into a HEF4520 counter and get the right signals on the output. All zeros (0 0 0 0) to all ones (1 1 1 1) is 16 different states, right? My problem is that I can't get channel 16 to work. I end up with channel 1 twice. It goes from channel 15 to channel 1. It seems like /\/\ can't do binary. 0 0 0 0 and 1 0 0 0 are the same to the CDM1250. Bummer

0 0 0 0 = channel 1 < something is wrong here
1 0 0 0 = channel 1
0 1 0 0 = channel 2
1 1 0 0 = channel 3
0 0 1 0 = channel 4
1 0 1 0 = channel 5
0 1 1 0 = channel 6
1 1 1 0 = channel 7
0 0 0 1 = channel 8
1 0 0 1 = channel 9
0 1 0 1 = channel 10
1 1 0 1 = channel 11
0 0 1 1 = channel 12
1 0 1 1 = channel 13
0 1 1 1 = channel 14
1 1 1 1 = channel 15

I have tried active low and active high with the same results. I just can't get 16 different channels.

Under the 'Default' accessory pin package,
I am using pins 3 (Channel Select 4 (input)), 6 (Channel Select 3 (input)), 8 (Channel Select 2 (input)) and 12 (Channel Select 1 (input)).

I am using R06.11.05 CPS.

Am I doing something wrong?

Inquiring minds want to know.

Thanks for your consideration in this matter

Chuck
KC2QPD

[jackhackett]

I believe all zeros goes to something like the last channel selected from the front panel, can't recall exactly...


edit... I knew I'd seen it somewhere, see humhead's response about halfway through

http://batboard.batlabs.com/viewtopic.php?f=1&t=64032

[cwolf520]

Thanks Jack. I got the system working. Thank GOD that I only need to exercise 8 channels.