//powers up the 24L01 with all necessary delays
//this function takes the existing contents of the CONFIG register and sets the PWR_UP
//the argument rx_active_mode is only used if the user is setting up the
// 24L01 as a receiver. If the argument is false, the receiver will remain in
// standby mode and not monitor for packets. If the argument is true, the CE
// pin will be set and the 24L01 will monitor for packets. In TX mode, the value
// of this argument is insignificant.
//note: if the read value of the CONFIG register already has the PWR_UP bit set, this function
// exits in order to not make an unecessary register write.
void nrf24l01_power_up(bool rx_active_mode)
{
unsigned char config;
nrf24l01_read_register(nrf24l01_CONFIG, &config, 1);
if((config & nrf24l01_CONFIG_PWR_UP) != 0)
return;
config |= nrf24l01_CONFIG_PWR_UP;
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
delay_us(1500);
if((config & nrf24l01_CONFIG_PRIM_RX) == 0)
nrf24l01_clear_ce();
else
{
if(rx_active_mode != false)
nrf24l01_set_ce();
else
nrf24l01_clear_ce();
}
}
//powers down the 24L01
//this function allows the user to set the contents of the CONFIG register, but the function
// clears the PWR_UP bit in the CONFIG register, so the user does not need to.
void nrf24l01_power_down_param(unsigned char config)
{
config &= (~nrf24l01_CONFIG_PWR_UP);
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
nrf24l01_clear_ce();
}
//executes the R_RX_PAYLOAD instruction
//unsigned char * data is the actual payload that has been received by the nrf24l01.
// The user must size data according to the payload width specified to the nrf24l01.
// This variable is filled by this function, so individual byte values need not be
// initialized by the user.
//unsigned int len is the length of the payload being clocked out of the nrf24l01 (this
// should be sized according to the payload length specified to the nrf24l01).
//returns the value of the STATUS register
unsigned char nrf24l01_read_rx_payload(unsigned char * data, unsigned int len)
{
unsigned char status;
nrf24l01_clear_ce();
status = nrf24l01_execute_command(nrf24l01_R_RX_PAYLOAD, data, len, true);
nrf24l01_set_ce();
return status;
}
//powers up the 24L01 with all necessary delays
//this function allows the user to set the contents of the CONFIG register, but the function
// sets the PWR_UP bit in the CONFIG register, so the user does not need to.
//the argument rx_active_mode is only used if the user is setting up the
// 24L01 as a receiver. If the argument is false, the receiver will remain in
// standby mode and not monitor for packets. If the argument is true, the CE
// pin will be set and the 24L01 will monitor for packets. In TX mode, the value
// of this argument is insignificant.
void nrf24l01_power_up_param(bool rx_active_mode, unsigned char config)
{
config |= nrf24l01_CONFIG_PWR_UP;
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
Delay_US(1500);
if((config & nrf24l01_CONFIG_PRIM_RX) == 0)
nrf24l01_clear_ce();
else
{
if(rx_active_mode != false)
nrf24l01_set_ce();
else
nrf24l01_clear_ce();
}
}
//sets up the 24L01 as a transmitter
//this function takes the existing contents of the CONFIG register and simply
// clears the PRIM_RX bit in the CONFIG register.
//note: if the read value of the CONFIG register already has the PRIM_RX bit cleared, this
// function exits in order to not make an unecessary register write.
void nrf24l01_set_as_tx()
{
unsigned char config;
nrf24l01_read_register(nrf24l01_CONFIG, &config, 1);
if((config & nrf24l01_CONFIG_PRIM_RX) == 0)
return;
config &= (~nrf24l01_CONFIG_PRIM_RX);
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
nrf24l01_clear_ce();
}
//powers down the 24L01
//this function takes the existing contents of the CONFIG register and simply
// clears the PWR_UP bit in the CONFIG register.
//note: if the read value of the CONFIG register already has the PWR_UP bit cleared, this
// function exits in order to not make an unecessary register write.
void nrf24l01_power_down()
{
unsigned char config;
nrf24l01_read_register(nrf24l01_CONFIG, &config, 1);
if((config & nrf24l01_CONFIG_PWR_UP) == 0)
return;
config &= (~nrf24l01_CONFIG_PWR_UP);
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
nrf24l01_clear_ce();
}
//sets up the 24L01 as a receiver with all necessary delays
//this function takes the existing contents of the CONFIG register and sets the PRIM_RX
// bit in the CONFIG register.
//if the argument rx_active_mode is false, the receiver will remain in standby mode
// and not monitor for packets. If the argument is true, the CE pin will be set
// and the 24L01 will monitor for packets.
//note: if the read value of the CONFIG register already has the PRIM_RX bit set, this function
// exits in order to not make an unecessary register write.
void nrf24l01_set_as_rx(bool rx_active_mode)
{
unsigned char config;
unsigned char status;
status = nrf24l01_read_register(0, &config, 1);
if((config & nrf24l01_CONFIG_PRIM_RX) != 0)
return;
config |= nrf24l01_CONFIG_PRIM_RX;
nrf24l01_write_register(nrf24l01_CONFIG, &config, 1);
if(rx_active_mode != false)
nrf24l01_set_ce();
else
nrf24l01_clear_ce();
}
//transmits the current tx payload
void nrf24l01_transmit()
{
nrf24l01_set_ce();
delay_us(10);
nrf24l01_clear_ce();
}
//takes a 24L01 that is already in active RX mode and puts it in RX standy mode
void nrf24l01_rx_active_to_standby()
{
nrf24l01_clear_ce();
}
//transmits the current tx payload
void nrf24l01_transmit()
{
nrf24l01_set_ce();
Delay_US(10);
nrf24l01_clear_ce();
}
