Haptic Feedback Case: The Firmware

The haptic feedback case is a shell that attaches to most modern android phones, it interfaces the user through positional and pressure input on the sides and rear of their device.

This firmware is to be programmed to the rev.10 board designed and developed by Ben Kazemi.

Dependencies

• WinAVR or derivative package to build .hex
• avrdude or alternative to program .hex

Build

The makefile is currently defined to program the board via ArduinoISP, and must have the communication port configured appropriately.

make clean
make 
make program

TODO List:

• fix headers and includes to make new makefile compile the code
• put source data into src folder
• re-write the serial lib
• interrupt driven uart
• interrupt driven ADC (unnecessary due to the structure of the program, hardware setup is defined, then ADC is read with processing based on the reading done immediately after - an interrupt driven ADC doesn't fit into this structure as you cannot set the ADC earlier in the code as the hardware is constantly changing with the Multiplexer etc)
• add rx to implement sensor selection on tx, & to turn all sensors off
• related to above point: have a boolean for each sensor, initialises to 0. host sends value that determines (bits of a byte) what sensors to activate. main.c cycles this byte - you can determine what sensors you're reading since you know the initial value, and from there, the host takes control of the byte
• echo back a sensor state change ONLY IF IT'S CHANGED on the rx and assert it's the same as the hosts Tx, else host receives an illegal number to signify a false reading, return error message and try again

this is taken out since it's been deemed unnecessary considering the data will be travelling through a wired medium

• test rx with computer terminal
• Add sleep states at off state
• When all sensors are off then disable adc spi & timers
• manually ground all inputs and outputs to uC (except TX RX) to keep current draw to a minimum
• decrease the clock when sleeping (don't brick your hardware ben)
• decrease the baud rate when sleeping
• turn decoder for mux all low if not 0b00010000
• move all sleep code to sleep.c and talk to it via sleep.h

License

This code is available under the GNU V3 license.