Hi Guys,
Not sure how well a question like this will be fielded on here, as its not so common!
I am working on a project (still) which I had intially intended to read data off a CAN bus (1mbit) and display on an LCD. Wisdom shone down upon me and I realized how much more effective it would be to instead use a Bluetooth module and communicate with an Android device and use that to display my data. I am planning to use the Bluetooth in SPP mode and just shoot the data via UART from a PIC32 MCU.
After abusing google & reading many data sheets, I am tossing up between going for a Bluetooth module version 2.1 + EDR (3mbit, to give me the overhead above CAN speeds) or Bluetooth 4.1 (24mbit).
Off the bat, BT 4.1 looks like the logical choice (being newer tech), but I want my device to be able to work with as wide a range of Android devices as possible. I don't need massively high speeds, and it is unlikely that even though the CAN bus will operate at 1mbit speeds, the FIFO buffers will ever have much in them.
The issue is older hardware, not so much software. I am not sure how backwards compatible BT 4.1 is with BT 3.0, 2.1 & 2.0 hardware based devices? Does anyone have any experiences with this? I can see that BT 4.1 is backwards compatible with 3.0, but not so clear whether this also applies to 2.1 and 2.0.
I am also concerned if I go with an older BT 2.1 + EDR device ( Like the Microchip RN41) that it might be a just a pointless exercise using aging tech and I wont be gaining any compatibility or ease advantage.
I think BT 2.1 + EDR would be most ideal (as it appears to still be by far the most popular) but I am not experienced with this sort of stuff, so if anyone has an opinion they can share I would love to hear it.
Cheers,
Hayden