Post by thread:[PIC] Bluetooth solution for serial communications

To follow up on my research into this question: I am now looking at possible solutions from National Semi. Since my only requirement is for SPP support (Serial Port Profile) a device like the LMX9830 looks interesting. It is a complete solution, including antenna and a UART interface to the microcontroller. And at only $7.50 a pop in quantity, the price seems right. Any thoughts? >From their product description at http://tinyurl.com/3yo5fu: "All hardware and firmware is included to provide a complete solution from antenna through the complete lower and upper layers of the Bluetooth stack, up to the application including the Generic Access Profile (GAP), the Service Discovery Application Profile (SDAP), and the Serial Port Profile (SPP). The module includes a configurable service database to fulfil service requests for additional profiles on the host. Moreover, the LMX9830 is pre-qualified as a Bluetooth Integrated Component. Conformance testing through the Bluetooth qualification program enables a short time to market after system integration by insuring a high probability of compliance and interoperability. "Based on National's CompactRISC(r) 16-bit processor architecture and Digital Smart Radio technology, the LMX9830 is optimized to handle the data and link management processing requirements of a Bluetooth node. "The firmware supplied in the on-chip ROM memory offers a complete Bluetooth (v2.0) stack including profiles and command interface. This firmware features point-to-point and point-to-multipoint link management supporting data rates up to the theoretical maximum over RFComm of 704 kbps (Best in Class in the industry). The internal memory supports up to 7 active Bluetooth data links and one active SCO link. " -- DC French

part 1 1903 bytes content-type:text/plain; format=flowed; charset="iso-8859-1"; (decoded 7bit) Don French wrote: > I am now looking at possible solutions from National Semi. Since my > only requirement is for SPP support (Serial Port Profile) a device > like the LMX9830 looks interesting. It is a complete solution, > including antenna and a UART interface to the microcontroller. And at > only $7.50 a pop in quantity, the price seems right. Any thoughts? Besides being Class 2, I think the two biggest problems are that the unit is not self-contained (it doesn't have a build-in antenna), and as a result you'll have to pay to get it certified ($$$). Please do let me know what you find out, as we may need a Class 2 module for future designs. On a related note, we've just tested the STM4100 module and the host board, and were able to achieve a range of 70 m (device sitting on the test bench, in the lab). I'm sure in situations with a direct line of sight, the range will be at least 100 m (stay tuned for updates). Here are some quick-and-dirty pictures of the prototype: <www.scantool.net/pub/stm4100/stm4100_bottom.jpg> <http://www.scantool.net/pub/stm4100/stm4100_top.jpg> I will make a post in [AD] next week, once we put together the spec sheet. The STM-4100 will be used to replace the blue "fish tail" in this picture: <http://www.scantool.net/products/images/images_big/elmscan5wireless_web_big.jpg> The cool thing is, switching from BT to RS232 is completely hands-free: the BT module "knows" when a serial cable is plugged in, and tristates the Tx line. The "Power" LED functionality is pretty nice too: - When the module isn't in, it's red - When the module is plugged in, but no BT connection, flashing red/yellow - When BT connection is established, but port is not open, solid yellow - BT com port open, green Ya'll have a great weekend! Vitaliy part 2 5908 bytes content-type:application/octet-stream; (decode) part 3 6585 bytes content-type:application/octet-stream; (decode) part 4 35 bytes content-type:text/plain; charset="us-ascii" (decoded 7bit)

On 9/3/07, Don French <spam_OUTdcfrenchTakeThisOuTgmail.com> wrote: > To follow up on my research into this question: > > I am now looking at possible solutions from National Semi. Since my > only requirement is for SPP support (Serial Port Profile) a device > like the LMX9830 looks interesting. It is a complete solution, > including antenna and a UART interface to the microcontroller. And at > only $7.50 a pop in quantity, the price seems right. Any thoughts? > I do not know much about Bluetooth but I tend to believe National's MCU busines is in limbo and the CompactRISC and COP8 are no longer promoted by National. So it is kind of risky to use the bluetooth moduce based on them. Xiaofan

Vitaliy wrote: {Quote hidden}> Don French wrote: >> I am now looking at possible solutions from National Semi. Since my >> only requirement is for SPP support (Serial Port Profile) a device >> like the LMX9830 looks interesting. It is a complete solution, >> including antenna and a UART interface to the microcontroller. And at >> only $7.50 a pop in quantity, the price seems right. Any thoughts? > > Besides being Class 2, I think the two biggest problems are that the > unit is not self-contained (it doesn't have a build-in antenna), and > as a result you'll have to pay to get it certified ($$$). Please do > let me know what you find out, as we may need a Class 2 module for > future designs. > > On a related note, we've just tested the STM4100 module and the host > board, and were able to achieve a range of 70 m (device sitting on the > test bench, in the lab). I'm sure in situations with a direct line of > sight, the range will be at least 100 m (stay tuned for updates). > > Here are some quick-and-dirty pictures of the prototype: > > <www.scantool.net/pub/stm4100/stm4100_bottom.jpg> > <http://www.scantool.net/pub/stm4100/stm4100_top.jpg> > > I will make a post in [AD] next week, once we put together the spec > sheet. > > The STM-4100 will be used to replace the blue "fish tail" in this > picture: > > <http://www.scantool.net/products/images/images_big/elmscan5wireless_web_big.jpg> > > > The cool thing is, switching from BT to RS232 is completely > hands-free: the BT module "knows" when a serial cable is plugged in, > and tristates the Tx line. > > The "Power" LED functionality is pretty nice too: > > - When the module isn't in, it's red > - When the module is plugged in, but no BT connection, flashing > red/yellow > - When BT connection is established, but port is not open, solid yellow > - BT com port open, green > > Ya'll have a great weekend! > > Vitaliy I might be interested in something along these lines later on. Just a thought turn the led off when tx or rx is in progress (if its handy). That way you know that data is actually travelling.

>Besides being Class 2, I think the two biggest problems are that the unit is >not self-contained (it doesn't have a build-in antenna), and as a result >you'll have to pay to get it certified ($$$). Please do let me know what you >find out, as we may need a Class 2 module for future designs. The statement that the National Semi device (LMX9830) is Class 2 is correct but the following description of this unit appears to say that it includes an antenna. Am I misreading it? "The National Semiconductor LMX9830 Bluetooth Serial Port module is a highly integrated Bluetooth 2.0 baseband controller and 2.4 GHz radio, combined to form a complete small form factor (6.1 mm x 9.1 mm x 1.2 mm) Bluetooth node. All hardware and firmware is included to provide a complete solution from antenna through the complete lower and upper layers of the Bluetooth stack, up to the application including the Generic Access Profile (GAP), the Service Discovery Application Profile (SDAP), and the Serial Port Profile (SPP). " And doesn't the FCC have to certify anything that you sell regardless of whether the component parts are already certified? At least that was what I was told by one person. I don't have personal experience with this. In any case I will certainly be interested to take a look at the datasheet for the STM-4100 once you have it available. -- Don

Its pretty much true...NSC isn't supporting new designs and actually discourages selling the COPs parts. Call up your local rep and have a discussion with them about it. This info came from my Arrow guy Don French <.....dcfrenchKILLspam@spam@gmail.com> wrote: >I do not know much about Bluetooth but I tend to believe >National's MCU busines is in limbo and the CompactRISC and >COP8 are no longer promoted by National. So it is kind of >risky to use the bluetooth moduce based on them. Xiaofan, do you have a source for this?

On 9/10/07, alan smith <micro_eng2KILLspamyahoo.com> wrote: > Its pretty much true...NSC isn't supporting new designs and actually discourages selling the COPs parts. Call up your local rep and have a discussion with them about it. This info came from my Arrow guy I thought the COPS stuff was dying back in the 80's. It must have been a very painful and agonizing death. I only knew one company using them, ONLY because they got the chips dirt cheap.

Jake Anderson wrote: > I might be interested in something along these lines later on. Just a > thought turn the led off when tx or rx is in progress (if its handy). > That way you know that data is actually travelling. Sorry, that doesn't fit well with our design. We already have two sets of Tx/Rx lights (see the scan tool picture). We were thinking about putting an SMD LED on a future revision, in case there is interest. Vitaliy

Don French wrote: > The statement that the National Semi device (LMX9830) is Class 2 is > correct but the following description of this unit appears to say that > it includes an antenna. Am I misreading it? > > "The National Semiconductor LMX9830 Bluetooth Serial Port module is a > highly integrated Bluetooth 2.0 baseband controller and 2.4 GHz radio, > combined to form a complete small form factor (6.1 mm x 9.1 mm x 1.2 > mm) Bluetooth node. > > All hardware and firmware is included to provide a complete solution > from antenna through the complete lower and upper layers of the > Bluetooth stack, up to the application including the Generic Access > Profile (GAP), the Service Discovery Application Profile (SDAP), and > the Serial Port Profile (SPP). " I think the key here is "FROM the antenna". They don't count the PCB as being part of the hardware. > And doesn't the FCC have to certify anything that you sell regardless > of whether the component parts are already certified? At least that > was what I was told by one person. I don't have personal experience > with this. If you use a self-contained module (that includes the antenna) in your design, you don't need to recertify the device with the FCC. Otherwise, it would quickly get to the point of ridiculous: Dell would have to recertify its computers every time a new WiFi card came on the market. Harold Hallikainen can authoritatively confirm or deny the above statement. :) > In any case I will certainly be interested to take a look at the > datasheet for the STM-4100 once you have it available. Sure thing, we should have it ready in a few days. Vitaliy

Jake Anderson wrote: >> The "Power" LED functionality is pretty nice too: >> >> - When the module isn't in, it's red >> - When the module is plugged in, but no BT connection, flashing >> red/yellow >> - When BT connection is established, but port is not open, solid yellow >> - BT com port open, green >> [snip] > Just a > thought turn the led off when tx or rx is in progress (if its handy). > That way you know that data is actually travelling. Sorry, I just realized that what I have said above (regarding LED functionality) is confusing. The "Power" LED is part of the scan tool, not the STM-4100. Currently, the BT module has *no* LEDs.

>> >> In any case I will certainly be interested to take a look at the >> >> datasheet for the STM-4100 once you have it available. >> > >> > Sure thing, we should have it ready in a few days. >> > >> > Vitaliy >> >> me too >> Cedric I just made a post in [AD], here's the datasheet: http://www.scantool.net/files/pdf/stm4100/stm4100.pdf If anyone thinks they can produce these cheaply in small quantities, please let me know. Most contract manufacturers we've contacted so far, want an arm and a leg (currently we're setting up to produce these in-house). Vitaliy

Cedric Chang wrote: > The spec sheet does not say what level the TX and RX are at. * > I presume the levels are 3.3 V. > > The spec sheet does not say what the max baud rate is. * > > * or at least I could not find it. Good points. Both Tx and Rx are TTL/CMOS compatible. The Tx is actually an output of a 74LVC240, which gets its power from Vsup (+5V in our case). Rx is fed through a 1K/1K divider. Default baud rate is 38K4, but the module supports 1.2K to 3Mbps (software configurable). By the way, I should mention that the LOS range has been empirically tested, and is really 330 ft (with our best BT dongle). Communication is possible even beyond 330 ft, but then packets start getting dropped, etc. I will update the datasheet tomorrow, thank you for the feedback. Vitaliy

On 5 Oct 2007 at 14:47, Vitaliy wrote: > Mark Jordan wrote: > > What will be the range when the module is inside a large metal box? > > You mean, a car? > > I'm not sure, I guess it depends. Can you give me the particulars? > I mean an industrial equipment installed inside a 50x40x20cm metallic box with no openings. Maybe I could make a hole for the BT antenna see the exterior. A range of a few meters would be sufficient. Mark Jordan

enkitec@gmail.com wrote: >> Mark Jordan wrote: >> > What will be the range when the module is inside a large metal box? >> >> You mean, a car? >> >> I'm not sure, I guess it depends. Can you give me the particulars? >> > > I mean an industrial equipment installed inside > a 50x40x20cm metallic box with no openings. > Maybe I could make a hole for the BT antenna > see the exterior. > A range of a few meters would be sufficient. We've never tested the module under such conditions, but you can't expect any RF to permeate a metal box with no openings. My suggestion would be, get a sample and test it for yourself to see how big of a hole you'd need for your situation. It's very easy, all you need to do is provide is a 5V supply, and short Tx/Rx lines together for a loop test. Vitaliy