Help! Needing hint on Microcontroller

You are unlikely to be able to make the modules in less than 100 off quantities for less than the off the shelf systems.

If you intend to use the same PCB at both ends, you will be wasting money, and board real-estate.

Any chip can be programmed in a high level language if you buy the suitable compiler. The part of this that will be incredibly difficult, is talking to the 'cheap USB-Bluetooth module'. USB, is a master-slave interface. The PC implements the master, and the master device is relatively complex, and needs a _lot_ of code. Slaves are cheap to implement. The USB-bluetooth interface, is a slave device. There are dozens of processors that offer USB-slave interfaces, but a USB master interface (which is what you would need to talk to such a device), will involve adding a master interface chip, and programming this. You can reckon on perhaps 60 man days of programming to implement such an interface. Much cheaper to use a Bluetooth module that is designed to interface to a microprocessor. These will cost more, but will bring the amount of code down to a few man-hours of work. A typical module would be:

TDK do cheaper version, that require a little more work. There are also such units, with a processor built in, like:

Best Wishes

Hello all!

Due to the costs and size of multichannel I/O RC-model Transmitters & Receivers I want to design a Bluetooth using, microcontroller based remote control. The pcb's in the receiver and the transmitter shall be equal, as there is a lot of data to be picked up and put out on both sides, as the vehicle has compass and tilt sensor, battery monitor and similar equipment, and the transmitter has to display these info's on both analoguous and digital displays.

What I am still thinking about is the main microcontroller on both sides - ideally it's a µC with a USB-Interface to make use of a cheap USB-Bluetooth-module, I would need about 8 output ports to act as servo-data lines, 4 to 8 digital inputs and at least 4 analog inputs. Furthermore the controller needs to be in-system programmable and ideally programmable with some higher-level language such as C or C++ or even Java.

Any ideas anyone? Input warmly welcome!

--
Sincerely

Ruediger

I thought so too. The model will be out of control range in no time at all.

Graham

I believe you are confusing the ZigBee radio parameters with some other proprietary radio solution. The IEEE 802.15.4 radios used in ZigBee networks are capable of operating at 868, 900 or 2450MHz at data rates of

20, 40 or 250 kilobits per second, respectively.

Compared to Bluetooth, I agree that ZigBee or a proprietary protocol using IEEE 802.15.4 radios may be suitable for this application.

I believe the spec calls for 3 output power levels. The largest, 100mW, is said to be about 100 meters or 300 ft and I've heard of enhancements to go further. It's still not enough for an RC plane (perhaps helicopter) but may be enough for a ground vehicle.

Robert

Ah, there it is. A 1.08 Mile Bluetooth range. Admittedly, in special circumstances.

Robert

I'm using a bluetooth module (TDK / Ezurio) and it runs out of steam at about 30 metres with no obstructions (admittedly with lots of metal surrounding the overall pair). At 2.4GHz and a low power level, obstructions (such as trees..) significantly reduce the range. At higher ranges, you have to reduce the data rate in cable replacement mode (the mode the OP apparently would use), so it would depend on the data rate necessary.

Ordinary modules - well, the ones I have tested - can't be trusted beyond about 10 metres for PCM (up to 192kbit/sec) unless you happen to have perfect atmospherics and no obstructions :)

Cheers

PeteS

ote

is a

as

s -

ly

ava.

A USB-bluetooth interface requires a USB master controller, meaning the functionality of a PC. How will you be communicating with the Bluetooth module without the windows driver ?

Beside that BT was never meant for longer range than a few meter.

A possible solution may be Zigbee @ 430MHz and 70kbit throughput.

But again, this stuff is much more expensive to develop than getting a functional unit.

Rene

--=20 Ing.Buero R.Tschaggelar -

& commercial newsgroups -

The ZigBee specification version 1.0 builds directly on top of the MAC and PHY layers described by IEEE 802.15.4. On page 29, Table 1 of IEEE

802.15.4-2003, only two PHYs are listed, one for the 868/915MHz bands and one for the 2450MHz band. The ZigBee specification version 1.0 document 053474r06 similarly says the same thing in the introduction on lines 42-45 of page 17. The 430MHz radios you've seen are definitely not ZigBee compliant, compatible or related in any away.

If you have a link to any vendors selling 430MHz ZigBee radios, I'd love to see it. I'd derive humor from seeing it, but primarily, I'd like to see it because all low power consumer type radios are interesting to me.

Some transmitters are able to use the 430MHz band. That may be different in the US vs Europe.

Rene