TUM/2015/ppc/README.mkd

# GPS on CAN

In this task you will need to receive Can-frames on the can-bus that contain the GPS location of the
vehicle. The raw data has to be converted to arc-milliseconds

    1°2'5" == (1*3600+ 2*60 + 5)*1000

**Beware that the system you are running your code on will not support floating point operations.
Use only unsigned and signed integers!**
Still the precision of your calculations has to be +-100 milli-arc-seconds

Dynamic allocation is not supported on the system.

You will have to complete the *GpsConverter.cpp* (and .h).


## Conversion to Arc-Degree

inDegree hex = 180/(2^31-1) * (hex) [°]

#### HINT 1

Try to use constants as much as possible, isntead of computing stuff on the go. 

#### HINT 2

In order to aviod losing decimals first multiply with a large factor and then divide to get the result in ms.

## GPS Datalayout in CAN Message

		Byte7 ST_LAT_NAVI
		Byte6 ST_LAT_NAVI
		Byte5 ST_LAT_NAVI
		Byte4 ST_LAT_NAVI
		Byte3 ST_LONG_NAVI
		Byte2 ST_LONG_NAVI
		Byte1 ST_LONG_NAVI
		Byte0 ST_LONG_NAVI

## Byteorder

Little Endian (Least Significant Byte is at lowest address)

## Status Longitude Navigation

		ST_LONG_NAVI

### Possible Values

		-180° ...  +180°

### Signal type

32 Bit Signed Integer (Byte 0 ... Byte 3)

### Invalid Data

Invalid-Value: 80 00 00 00h

Signal not available value: 7F FF FF FF

**Do not forget to check for these values**

## Status Latitude Navigation

		ST_LAT_NAVI

### Possible Values

		-180° ...  +180°

### Signal type

32 Bit Signed Integer (Byte 4 ... Byte 7)

### Invalid Data

Invalid-Value: 80 00 00 00h
Signal not available value: 7F FF FF FF

## Send the data over to the AC

Use the *IGpsACPusher*.

## Running the tests

you will need a working ruby installation to execute the tests

### run the tests

execute `rake run` from this directory

### Install the bake tool

see https://esrlabs.com/gems/doc/bake-toolkit/