extern void Nrf24l::getData(uint8_t * data)
// Reads payload bytes into data array
//读RX 有效数据：1-32 字节。读操作全部从字节0 开始。当读RX
//有效数据完成后，FIFO 寄存器中有效数据被清除。
//应用于接收模式下。
{
csnLow(); // Pull down chip select
spi->transfer( R_RX_PAYLOAD ); // Send cmd to read rx payload
transferSync(data,data,payload); // Read payload
csnHi(); // Pull up chip select
// NVI: per product spec, p 67, note c:
// "The RX_DR IRQ is asserted by a new packet arrival event. The procedure
// for handling this interrupt should be: 1) read payload through SPI,
// 2) clear RX_DR IRQ, 3) read FIFO_STATUS to check if there are more
// payloads available in RX FIFO, 4) if there are more data in RX FIFO,
// repeat from step 1)."
// So if we're going to clear RX_DR here, we need to check the RX FIFO
// in the dataReady() function
// NVI：每个产品的规格，第67页，注三：
//“的RX_DR IRQ是断言一个新的数据包到达事件的过程
//处理这个中断应该是：1）通过SPI读取有效负载，
//2）明确RX_DR IRQ，3）读FIFO_STATUS，以检查是否有更多的
//在RX FIFO中可用的有效载荷，4）如果在RX FIFO更多的数据，
//重复从步骤1开始）。“
//所以，如果我们要在这里清除RX_DR，我们需要检查RX FIFO
//在dataReady（）函数
configRegister(STATUS,(1<<RX_DR)); // Reset status register
}
void Nrf24l::readRegister(uint8_t reg, uint8_t * value, uint8_t len)
// Reads an array of bytes from the given start position in the MiRF registers.
{
csnLow();
spi->transfer(R_REGISTER | (REGISTER_MASK & reg));
transferSync(value,value,len);
csnHi();
}
extern void Nrf24l::getData(uint8_t * data)
// Reads payload bytes into data array
{
csnLow(); // Pull down chip select
spi->transfer( R_RX_PAYLOAD ); // Send cmd to read rx payload
transferSync(data,data,payload); // Read payload
csnHi(); // Pull up chip select
// NVI: per product spec, p 67, note c:
// "The RX_DR IRQ is asserted by a new packet arrival event. The procedure
// for handling this interrupt should be: 1) read payload through SPI,
// 2) clear RX_DR IRQ, 3) read FIFO_STATUS to check if there are more
// payloads available in RX FIFO, 4) if there are more data in RX FIFO,
// repeat from step 1)."
// So if we're going to clear RX_DR here, we need to check the RX FIFO
// in the dataReady() function
configRegister(STATUS,(1<<RX_DR)); // Reset status register
}
