I just bought a BRAT and was at first a little annoyed by the lack of information on the Bluetooth dongle that came with it. It is made by Cambridge Radio and took me a lot of time and MANY forum searches to find the real drivers for it. Now I have them, and I am running into another problem. The Bluetooth board that came with the SCS is manufactured badly, causing the Bluetooth module to not be able to sit flat in the socket as there is something in one of the socket headers…maybe a solder spill over.
When I plug everything in, the Bluetooth board does receive power, but the RSSI light is on a slow pulse when in AT mode and a fast pulse otherwise, and the PC does not see it at all, so none of the software works.
I would like to get to using the bot this weekend as I haven’t used it at all yet, other than building it. I could replace the header as I have some stock headers of the same size (for my XBee projects), but honestly I’m just not confident in the comms hardware.
So a couple of questions:
So…do I abandon that and just use XBee and Arduino?
Do I need the serial cable at all (initial setup, etc.) ?
EDIT: ok, I managed to ream out the bad header socket and I can now get a connection between the PC and the Bluetooth Xbee, but the sequencing software still does not see the SCC-32.
I have checked that the com port is 15.2k and that both jumpers are set on the SSC-32, but still nothing.
EDIT: OK, so now I can get the BT board talking to my PC and I can use Lynxterm to send data to the board, and that part works. The problem right now is that outside of Lynxterm nothing else can communicate with the board. None of the provided software, or writing serial data from my Arduino to the board works. With the Arduino I was sending serial data like "#0 P1600 T1000 " and the BT board received the data, as can be seen by the LEDs, but the SSC board never does anything.
any thoughts?
This is seeming more and more like a sound board than a forum, but hey it’s progress.
Sorry, but I have not tried doing much yet with BT. I do have a BT module that plugs into an XBee, but still sitting in the wrapping. Also not sure if same one as you have. (Purchased mine from Sparkfun).
Maybe when some of the Lynxmotion people get in on Monday they will have more information.
As for SSC-32 seeing the data but not acting on it. This could be many different things. Like: The BT is not talking at the same baud rate as the SSC-32 is configured for. The LED on the SSC-32 will blink with data even when it is garbage.
Would probably help to have additional information like more on how these boards are wired together. Is it simply BT connected up to SSC-32? You mention Arduino, how is this involved? BT -> Arduino -> SSC-32? Which Arduino? What pins are connected to what…
Initially I was just using the BT board and BT Bee that came with it, connected directly to the SSC. In that configuration everything worked with Lynxterm, but not with the other supplied software (Visual Sequencer, etc.)
I opted not to use the BT in the end, but instead soldered a header onto the side of the BT board as per the board diagram, so that I can expose the functionality to the Arduino and then just use the BT board as a pass through. Then I wondered if I could just bypass the BT board altogether and hit the SSC board directly. Time to experiment to some.
By default, the Bluetooth bee modules is configured to run at 9600 baud. We generally recommend simply configuring the SSC-32 to use the same baud rate, but you can also use the AT mode of the BT bee module to change it to use 115.2k instead. Here is the BT module that’s included:
It’s odd that you could get it to work with Lynxterm but not the Visual Sequencer or FlowBotics. What baud rate did you end up using?
If you instead want to connect the serial of an Arduino Mega 2560 to the SSC-32 board, you can remove the RXTX jumpers and connect directly there instead. They are identified by number 14 in the SSC-32 manual:
What exactly is on the Atmel IC on the SSC? I’m curious to know if there is space on there for a sketch that will talk to an RF Xbee. It seems kind of silly to add an RF Xbee and an Arduino pro mini if there is already enough space on the connected IC. Although the separation of logic makes sense.
I am also fond of burning code to ATTiny chips so the use of RX/TX to/from the board is also great.
As for the Lynxterm/Flowbotics issue I am at a loss, but hey that’s learning.
The SSC-32 firmware code is a few thousand lines long, supporting all the servo move commands with durations, support for configurable registers, for hexapod sequencer commands, and all the stuff of the General Purpose sequencer. There is still some spare space on the chip, and the next version of the SSC-32 will likely have Xbee headers on board.
When using the SSC-32 board with the BT bee, did you have the SSC-32 configured at 9600? If you are trying the BT again, you can try using the free SSC-32 Servo Sequencer Utility to see if you get different results.
OK, I tried again with BT and seemed to get it working, but only so far in this combination of baud rates:
COM port: 115200
Software: 115200
SSC: 9600
If I change SSC by adding jumper 2 to set to 115200, I cannot establish a connection and the BlueSoleil software disconnects from the device.
Odd, but not a deal breaker as I prefer working with RF anyway.
The way that baud rates and BT works is a bit weird. Since the computer’s BT adapter is USB and there is no real serial link between it and the software, the baud rate specific in software is basically ignored. However, the link between the BT bee and the SSC-32 is RS-232 serial, so the baud rate of both the BT bee and the SSC-32 must be the same.
Changing the baud of the SSC-32 is easy through the baud jumpers, so that’s usually the approach we suggest: configured the SSC-32 to use 9600 to match the factory default of the BT bee. You can however change the BT bee’s baud rate by using the AT mode and send the
AT+BAUD8
command, which will configure the Bee to use 115,200. Once this is done, you can reinstall the jumpers on the SSC-32 so that it uses 115,200 also.
We generally don’t recommend this since it is a lot of work, is error-prone, and doesn’t give any real benefit, but it still never-the-less possible.
