So, after all of my experiments with BCM2042-based Bluetooth modules and the uncertainty and sparse documentation surrounding them, I decided to give Bluegiga’s WT12 module a try. I have to say, the more I learn and experiment, the more I like it. This one single module supports pretty much every Bluetooth profile ever, easily hot-switchable via a simple command. Their customer support is excellent. Their documentation, firmware, schematics, and all other development resources are readily available for free. Their modules are available for purchase cheaply in small quantities (e.g. one at a time for $27 from SemiconductorStore.com). You can control the complete behavior of the module using their capable iWRAP firmware and well-documented commands sent over the UART interface. It’s perfect.
I ordered a couple of WT12 breakout boards to go along with the two WT12 modules I ordered, but the boards are coming from BatchPCB which, while inexpensive, will take weeks to arrive, or so I’m told. So I went ahead and decided to solder wires directly onto the tiny solder pads on the WT12 itself. Of course, I forgot to notice that the datasheet diagram was showing the top view of the module, so I soldered everything (VDD, GND, TXD, RXD, RTS, CTS) onto the wrong sides. I didn’t catch that mistake for a couple of hours…oops. Fortunately, I didn’t fry anything, probably because the GND pin was still valid.
WRAP THOR AI (3.0.0 build 165) Copyright (c) 2003-2008 Bluegiga Technologies Inc. READY.
Yes! Yes yes yes yes YES! One very, very simple firmware update later via their SerialDFU utility (I ordered v3.0 modules because the v4.0 modules were out of stock), and I got this:
WRAP THOR AI (4.0.0 build 317) Copyright (c) 2003-2010 Bluegiga Technologies Inc. READY. at OK set SET BT BDADDR 00:07:80:44:a0:89 SET BT NAME WT12-A SET BT CLASS 001f00 SET BT IDENT BT:47 f000 4.0.0 Bluegiga iWRAP SET BT LAP 9e8b33 SET BT PAGEMODE 4 2000 1 SET BT POWER 3 3 3 SET BT ROLE 0 f 7d00 SET BT SNIFF 0 20 1 8 SET BT MTU 667 SET CONTROL BAUD 115200,8n1 SET CONTROL CD 00 0 SET CONTROL ECHO 7 SET CONTROL ESCAPE 43 00 1 SET CONTROL GAIN 0 5 SET CONTROL MSC DTE 00 00 00 00 00 00 SET CONTROL PREAMP 1 1 SET CONTROL READY 00 SET PROFILE SPP Bluetooth Serial Port
Now I can really have some fun.