' Written By:Dave Brown
' Date:      5-25-2008
' Program:   DJB-FM_transmitter.bas
'            Sets up NS73M module to transmit in stereo
'              102.9 megahertz
'              73 us pre-emphasis
'              2 milliwatts transmit power
'              200 millivolts audio input for 100% modulation.
'
' Compiler:  BASCOM-AVR IDE
' Processor: ATTINY13
'            Fuse programming
'              4.8 megahertz internal RC oscillator
'              brownout disabled
'
$regfile = "attiny13.dat"                                   'ATTINY13 processor
$crystal = 4800000                                          'Internal RC osc. fuse set to 4.8 megahertz
'
' NS73M read and write address
Const Fmtxwr = &B11001100                                   'Address and Write to FM Tx Module
Const Fmtxrd = &B11001101                                   'Address and Read from FM Tx Module

' Configure I2C pins
Config Scl = Portb.0                                        'Is serial clock SCL pin 5
Config Sda = Portb.1                                        'Is serial data SDA pin 6
'
Waitms 50                                                   'Wait for NS73M power up
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H0E                                               'Register E
I2cwbyte &H05                                               'Software reset
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H01                                               'Register 1
I2cwbyte &HB4                                               'Pilot on, forced subcarrier
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H02                                               'Register 2
I2cwbyte &H07                                               '2 mW power, Unlock detect on
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
' (102.9+.304)/0.008192=12598.14                             'Calculate for 102.9 MHz
' 12598=&H3136                                               'Low byte=&H36  high byte=&H31

I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H03                                               'Register 3
I2cwbyte &H36                                               'Lower byte frequency  (102.9 megahertz)
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H04                                               'Register 4
I2cwbyte &H31                                               'Upper byte frequency  (102.9 megahertz)
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
' Set up Bands based on the following ranges:
' Band (CEX)       3      2      1       0
' Frequency  87.5 --- 90 --- 95 --- 101 --- 108  MHz
' Band 3: 87.5 - 92     CEX=&H1B
' Band 2: 87.5 - 98.6   CEX=&H1A
' Band 1: 93.3 - 103.9  CEX=&H19
' Band 0: 99.3 - 108    CEX=&H18
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H08                                               'Register 8
I2cwbyte &H18                                               'CEX = Band 0
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H00                                               'Register 0
I2cwbyte &HA1                                               'Pwr on, 200 mV audio for 100% modulation
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H0E                                               'Register E
I2cwbyte &H05                                               'Software reset
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
I2cstart                                                    'I2C Start
I2cwbyte Fmtxwr                                             'I2C FMTx Slave Addr Write
I2cwbyte &H06                                               'Register 6
I2cwbyte &H1E                                               'Set internal charge pumps
I2cstop                                                     'I2C Stop
Waitms 1                                                    'Wait for it to process
'
Mcucr = &H38                                                'Prepare to sleep MCU
sleep                                                       'Sleeps processor
Do : Loop                                                   'Just in case it wakes up

End