If you have a Parallel port you could use the I/O pins there to do BCD assuming the SM120 can do it (which it looks like it can). It only requires 4 lines to
get 16 channels. To select a particular channel just set the line to the Binary equivalent.
|
|
Line |
Line |
Line |
Line |
|
Channel |
4 |
3 |
2 |
1 |
|
1 |
0 |
0 |
0 |
0 |
|
2 |
0 |
0 |
0 |
1 |
|
3 |
0 |
0 |
1 |
0 |
|
4 |
0 |
0 |
1 |
1 |
|
5 |
0 |
1 |
0 |
0 |
|
6 |
0 |
1 |
0 |
1 |
|
7 |
0 |
1 |
1 |
0 |
|
8 |
0 |
1 |
1 |
1 |
|
9 |
1 |
0 |
0 |
0 |
|
10 |
1 |
0 |
0 |
1 |
|
11 |
1 |
0 |
1 |
0 |
|
12 |
1 |
0 |
1 |
1 |
|
13 |
1 |
1 |
0 |
0 |
|
14 |
1 |
1 |
0 |
1 |
|
15 |
1 |
1 |
1 |
0 |
|
16 |
1 |
1 |
1 |
1 |
I do this with a commercial repeater controller and Kenwood TK-7180/8180 radios and it works great.
Jamey Wright
WR4JW
From: app_rpt-users-bounces@ohnosec.org [mailto:app_rpt-users-bounces@ohnosec.org]
On Behalf Of Skyler F
Sent: Wednesday, June 10, 2015 8:53 AM
To: app_rpt-users@ohnosec.org
Subject: [App_rpt-users] Remote Bases with 16 channel radios?
Has anybody ever created a remote base with a radio like the SM120 16 channel commercial radio? Would it be possible to use the URI to specify the channel I want to go to, for example, hooking a GPIO pin to the "channel -" button and hooking
another to the "channel +" button? So if I am on channel 1 and want to go to 7, the GPIO for "chan +" would have to pulse 6 times. That wouldn't be very reliable probably because there is no confirmation that you are actually on the right channel, but this
is how I would do it:
When a channel change is requested, pulse 16 or more times on the "chan -" button to make sure it is on channel 1. Then count the + button up to the channel number you want to go to. That idea, however wouldn't work on the SM120 because
going below channel 1 brings you back to 16.
Another idea I have is put one channel on a frequency reference (maybe those 150mhz re-broadcasts of radio stations?) and then find the channel you want based on that reference.
Another idea yet would be to use a few more GPIO pins to see which elements of the 7-segment displays are lit up and then make an estimate on which channel you currently are on.
Any other ideas?
73
Skyler kd0whb