to Sniff or to Pull! what is better...


ok, let me clear the elephant in the room, no I ain't sniffing anything...  other then in my coding...

The goal of this email is to open a discussion about how to reach CI-V information on a CI-V bus like the CT17Bs to use this information within your projects...

there are basically two ways of getting information from your radios for your applications or your hardware projects...


Pulling information from a CI-V based radio is done for most applications like HRD, Logger32, etc... but also by OEM hardware and many of our Hardware projects.

When you use a PULL method you are basically sending commands to the radio via your CI-V bus or USB port to get specific information like frequency, band, volume settings, voltage, etc...  the more advanced the application the more PULLing it will do.

- Accurate
- Low latency
- Great in a 1 to 1 environment.

- High usage of the CI-V Bus
- Pron to collision in multiple device environment

you see...  The reason why it is so low latency, is because most hardware or Application that use this will be polling, and the better ones with very latency like HRD use a LOT of polling...  and I mean a LOT!

that is why this is highly pron to collisions if in a multiple device environment... Works great in a 1 to 1 environment.


Sniffing is simple, if you have a multiple devices/Application environment on your CI-V bus, like Radio, HRD, Steppir, etc...  for example then if both HRD and the Steppir SDA100 are PULLING data from the radio there WILL be collisions and thus problems...

And if you don't have any application and are in a 1 to 1 environment then you MUST turn one CI-V transceive, CI-V transceive will make the radio send CI-V data on whatever is changed on the radio so that the SNIFFing device can get the info.

Mind you a lot of applications like to have CI-V transceive ON so that they can drop their latency even lower...  and this even if they are running PULL.

- Low collision (None!)
- Accurate as long as CI-V Tranceive is ON.

- Latency issues can be a problem.
- Must have Transceive ON, well in a single CI-V bus with multiple radios, this will cause ALLL radios to change info at the same time and you may not want that!

Hey, I probably forgot something important! would be interested to hear from you and your experience with this...  Join in!

Richard VE2DX, Jesus Island, PQ-014

Only the Best ICOM, ERC and HRD
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