I need do communicate atmega88 with a smartphone via bluetooth using a bluetooth HC-05 module. The problem is that all my atmega pins are being used. Rxd and txd pins are being used by a keypad (Keypad at PORTD). My project is almost done, at this stage i don't want to change the micro. Is there any alternative to solve this problem? Thanks
You can use Software serial library for that controller. But it is better to connect HC-05 module to default UART pins.
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I have a project where I am trying to use the adxl345 as a pedometer and it is hooked up to an Arduino where it will count steps.I also have a bluetooth device from Adafruit (nrf8001) that is hooked up to an Arduino.
I want to the Arduino to send the steps via bluetooth to an smart phone. The problem I am currently at is the Arduino can only use either the adxl345 or the nrf8001. I cannot have both using SPI communication. I know that SPI can have multiple devices attached to it using chip select. I am using slave select but I don't know why it is not working. According to Adafruit they use their own special SPI communication that not only uses chip select but also a reset and interrupt.
Read following page.
https://learn.adafruit.com/getting-started-with-the-nrf8001-bluefruit-le-breakout/pinouts
It's REQ pin is considered as chip select.
A number of bluetooth Arduino shields (Bluefruit EZ-link, SparkFun Bluetooth Silver) support DTR/RTS and have special out pin to wire. How do they work? Does it require special drivers (linux f.e.)? Can any bluetooth receiver be used or modified to provide DTR/RTS? Since setting DTR/RTS is vendor-specific does it depend on transmitter side or receiver (bluetooth shield) only?
The only idea is that special USB drivers needed that send special AT commands to make BT receiver know actual DTR/RTS value.
The documentation of Bluetooth SPP (https://developer.bluetooth.org/TechnologyOverview/Documents/SPP_SPEC.pdf) states in section 4.1 RS232 Control Signals that "all devices are required to send information on all changes in RS232 control signals".
And since Bluefruit EZ-link is not using any special drivers on the side of the computer, it must be that the standard BT virtual serial port drivers that manage the ports created for the BT connection to Arduino handle the control signals properly and send them over to the BT shield connected to Arduino. Hence no work should be needed on the side of the computer, and it only depends on the receiver: whether it has the control signals accessible on any of the output pins and operates them as it should, or not (as usually is the case, unfortunately).
Bluefruit EZ-link is described as programmer. It means it supports RTS/DTR:
The EZ-Link has another impressive feature: the DTR/RTS/DSR flow
control pins are automatically synced to the computer serial port.
What this means is that if the computer sets the hardware flow control
DTR or RTS pins high or low the pins on the bluetooth module will
follow.
So Arduino IDE performs reset to initiate flashing (as Arduino's Bootloader wait for few seconds after reset for upload commands from Arduino IDE). For USB reset works by switching DTR to 1 and 0 and special schematics on Arduino board monitors it and performs reset. After reset is done Arduino IDE runs avrdude and start flashing.
The question is "How does it works over Bluetooth module by Adafruit?" There is no RTS/DTR line for Bluetooth..
PS. I believe virtual COM-port drivers for this Bluetooth device should send special AT+ commands and Bluetooth device should handle them and perform setting 1 or 0 to special pin wired with MCUs reset. But this requires Bluefruit bluetooth driver to be used. But i can't see it requires special BT drivers at computer.
RFCOMM do support flow control.
RFCOMM is based on GSM TS 07.10. Bluefruit extract info on RFCOMM and map it to flow control lines.
I am trying to control the android music player from an Arduino with an HC-05 Bluetooth module. I have successfully paired them in serial mode but have been unable to find any means to connect them with the AVRCP profile. Is there a library that I can load into a sketch to do this?
The HC-05 supports SPP only. In order to get any other BlueTooth profile on there, you would have to create and flash different firmware for the Broadcom BC417143.
I have Firmata working fine on an Arduino Uno, communicating over cable USB to Processing.
I want to get rid of the cable, and run the connection over Bluetooth transport (with a BlueSMIRF module). I am unclear on what I need to do to Firmata to tell it to use the BT module rather than the (unconnected) USB cable interface. In particular, do I need to hack Firmata itself to add initialization code which is
specific to the BT module I'm using, or
more generally, needed to tell Firmata to use a port other than the cabled USB?
Thanks
D
I am NOT very good in Firmata, but as i know, Firmata (on arduino) uses 'Serial' (pin 0 and 1, also aka as TX,RX) to communication with the Host. So, if u want to use a BT module to replace your USB cable on the arduino, hack the Firmata to use other pins, other connect the BT to pin 0 and 1.
You have to upload standard firmata with baud rate changed to 9600 inside the ino file (or test with other speed rate) and then connect BTooth TX>Rx(uno RX) and the bt RX>Tx(uno TX) as said in the previous post ,testing it with arduinoCommander worked like a charm!Arduino uno rx tx are pin0 and pin 1.also have it powered not from usb pc but external source cause having the BT ontop while on usb could mess up thing (in general disconnect the ground from BT module while uploading sketches).
All you have to do is make sure the USB is connected only when you are uploading your sketches to the arduino and then have the BlueSMIRF connected when you are ready to actually run the Arduino code. This way they will both use the default hardware serial port and you should not have to modify any code.
You could try and use SoftwareSerial.h in the Arduino to emulate another serial port but I have found that to be problematic.
Just connect Bluetooth to the Rx Tx pin and upload same standard firmata. Then pass command over bluetooth which you were passing over usb cable....it wil work.