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Motorola Zaptor

Posted: Fri Feb 12, 2010 4:35 pm
by The Robman
I've just received some learns that are very similar to the Amino learns in this thread, which I was alerted to as they decoded as Amino, but there are differences.

The new learns are for a Motorola Zaptor. The freq is different (36k), the toggle bit is different and the checksum is different, but the overall structure is very similar. Oh yeah, the toggle doesn't flip every repeat like the Amino version does, this one sends out a post-repeat signal with the toggle flipped.

The following zip file contains the IR files, along with some other files that may be of interest. Please note however, that the included upgrade files have not been tested yet.

https://www.hifi-remote.com/forums/dload ... le_id=8016

Posted: Sun Feb 14, 2010 10:54 am
by mathdon
Rob, I see that you have the checksum as a data byte in your rmdu file. Compared with Amino, it is a trivial checksum to calculate. The high nibble is 5 and the low nibble is (mod 16) 5 more than the sum of the six nibbles in the device, subdevice and OBC codes. This deals with the change in the checksum in the toggle frame, as the toggle appears to be the top bit of subdevice.

What do you want to call this, if I put it into DecodeIR?

Edit: That high nibble of C is presumably the checksum seed. There's another protocol like that, but at present I can't remember which one.
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Graham

Posted: Sun Feb 14, 2010 11:50 am
by The Robman
I did that because I hadn't bothered to figure out the checksum yet, plus it's always a toss-up as to whether it saves memory to put the logic in the assembler or not, but it probably would use less memory in this case to code it. I might look into that later once I get confirmation that the upgrade actually works.

As for naming it, I'd really like to name it after the company who makes the remote chips, but of course we don't know who that is yet. So, if anyone wants to do some digging and find out who's supplying the chips in the Motorola Zaptor and Amino Aminet remotes, please let us know. In the meantime, I suppose we could call it "Zaptor".

Posted: Mon Feb 15, 2010 11:49 am
by mathdon
OK, I've put Zaptor into DecodeIR. I've treated it as having IRP

{36k,330,msb}<-1,1|1,-1>(8,-6,2,D:8,T:1,S:7,F:8,E:4,C:4,-74m)+

where T=0 for all frames except the last, T=1 for last frame, E is a checksum seed (reported in the Misc field if other than 5) and C is the sum of the previous 7 nibbles. The OBC values come out looking pretty random but I can't see any pattern in your spreadsheet that would suggest any better way of decoding them.
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Graham