#!/bin/python

from greatfet import GreatFET

gf=GreatFET()

def reset():
    gf.spi.transmit([0xc8])

def status():
    # Send a NOP and print the status byte response in hex.
    print(hex(gf.spi.transmit([0xff])[0]))

def ready():
    # Send RC_PHY_RDY.
    gf.spi.transmit([0xb3])

def tx():
    # Send RC_TX.
    gf.spi.transmit([0xb5])

def config_test():
    # See Transmit Test Modes on page 71 of data sheet.
    gf.spi.transmit([0x1b, 0xf0, 0x21]) # Set tx_fsk_test to unmodulated carrier
    gf.spi.transmit([0x19, 0x07, 0xb0]) # buffercfg
    gf.spi.transmit([0x19, 0x08, 0x0c]) # Set skip_synth_settle in pkt_cfg

# Set up GPIO pins used to configure the TX RF switch.
v1=gf.gpio.get_pin('J2_P19')
v2=gf.gpio.get_pin('J2_P23')
v3=gf.gpio.get_pin('J2_P25')
v4=gf.gpio.get_pin('J2_P27')
v1.set_direction(v1.DIRECTION_OUT)
v2.set_direction(v2.DIRECTION_OUT)
v3.set_direction(v3.DIRECTION_OUT)
v4.set_direction(v4.DIRECTION_OUT)

# To select the U1 TX path, write 1 to v1 and 0 to the others.
# For U2, write 1 to v2 and 0 to the others, etc.
v1.write(1)
v2.write(0)
v3.write(0)
v4.write(0)

# U1 chip select: J2_P9
# U2 chip select: J1_P14
# U3 chip select: J2_P7
# U4 chip select: J1_P34
#
# I've just been testing one chip at a time, so I have connected a jumper wire
# from one of the above pins to J1_P37 (SSEL).  Alternatively you can wrap
# spi.transmit() in a function that pulls down the appropriate chip select.

status()
reset()
status()
status()
config_test()
ready()
tx()
status()

# Status should now be 0xe5 which indicates TX is active.  If it doesn't go to
# 0xe5, try again.  (For reliability we probably need to confirm prior state
# changes before requesting another.)