Hello all,
I want to use one Sparkfun BlueSMiRF to control (without any wires) two cards with SPP (Serial Profile Port).
For example, one SSC-32 and and one EM2218C from Eletech
( follow this link : eletech.com/Products/Audio_R ⊠m2218c.htm )
I donât think so, but maybe I mistake me.
In advance, many thanks for your answer. (and sorry for my bad english)
James
There is a tutorial on the Lynxmotion website on how to use the blue smirf. I think it is one of the links on the brat page or it might be located in the BRAT assembly guide page.
Sorry I cant post a direct link to it. My work has blocked all .com sites.
Many thanks for your answer⊠but I have already reading the tutorial 
My problem is not to control my robot without any wires, but to control with one Sparkfun BlueSMiRF, two RS-232 card, like the SSC-32.
With Lantronix WiPort, itâs possible because the card had two RS-232 ports ( follow this link : lynxmotion.net/viewtopic.php ⊠=lantronix ), but I donât know if I make the same think with BlueSMiRF.
James
Hey James,
So you want to use one BlueSMiRF to control two serial devices? That is very possible and fairly simple.
You will need a microcontroller of some sort to read the BlueSMiRF. Connect both serial devices to the microcontroller. Then with the BlueSMiRF, before sending a command or signal send an address.
So, for example, you can make your SSC-32 0x32 and your EM2218C 0x22.
If you want to talk to the SSC-32, first send â0x32â The micro will then send back an ACK saying âIâm reading to talk to the SSC-32!â Once you get that ACK, you continue to send your commands to the SSC-32. The microcontroller will get the commands and fwd them to the SSC. To end communication, you can send something like âE 0x32â or simply â0x32â This will end the communication between bluetooth and the SSC-32.
There are possibly easier ways to do this⊠You can possibly send the address at the beginning of the command so you donât need to do a start/end session thing. You can simply be like:
0x32 move servos here
0x32 move more servos
0x22 do some sound stuff
0x32 reset servos
0x22 scream
etc.
You can possibly also create a switch of some sort which will direct the Rx/Tx lines of the bluesmirf based on which address you send first. I think the microcontroller catching the data and sending it to the correct device would be easier.
-robodude666
In fact, I think use microcontroleur is the best solution.
But, my big problem to use microcontroleur for my project is⊠I donât have microcontroleur programmer (for the moment only).
Actually, I search a low cost solution. I have found another bluetooth card with one serial port but compatible with SPP. This card is builded by Free2move ( follow this link : free2move.se/index.php?type= ⊠language=1 ) for only 25-30 euros.
But another problem : this card use only low voltage (3.1-3.6 V) or ultra low voltage for the last model. For solve this problem, I search a low cost voltage regulation circuit⊠low cost, only.
Wouldnât you also need two bluetooth transmitters on your computer? I heard bluetooth can only make one âlinkâ at a time. I might be wrong.
It depends on the Bluetooth module being used. Some can handle up to 8 links at a time.
8-Dale
Yes, for the moment, I want to use four transmetters (two on PC and two on the robot).
For solve the âlinkâ problem (if itâs relly a problem with my hardware), I think to use 2 low cost motherboards like mini-itx to build my big remote. If I build my own Robot Player in PHP, itâs only for solve this problem.
James
We were able to control two robots at the same time using the spark fun bluetooth module on a lap top. The two robots each had a blusmirf module connected to their SSC-32âs. We used two sessions of SEQ as the program to send the robots their position information. So I see no reason you couldnât control two devices using the one blutooth dongle.
Why did you use two sessions? If one instance of the SEQ software is sending information to the PCâs blue dongle, wouldnât each blue smirf module connected to seperate SSC-32âs recieve the same data at the same time? This would cause a sync type of movement though I would assume.
Right?
They probably had two different virtual com ports for the two BlueSmirfs. 
8-Dale
The test was to ensure the bluetooth dongle (and software) could talk to two separate bluesmirf devices at the same time, which it can. Not to see if one session of SEQ could send identical information to two separate robots, which I doubt if it could, because the modems are bidirectional.
