'------------------------------------------------------------------
'   Nordic nRF24L01 data link demo in Enhanced Shockburst mode
'        By Evert Dekker 2007 nRF24L01@Evertdekker dotje com
'                   Created with Bascom-Avr: 1.11.8.3
'------------------------------------------------------------------
$regfile = "M8535.dat"
$crystal = 8000000
$baud = 19200
$hwstack = 40
$swstack = 20
$framesize = 40

'=== Declare sub routines
Declare Sub R_register(byval Command As Byte , Byval C_bytes As Byte)
Declare Sub W_register(byval C_bytes As Byte)

'=== Constante ===
'Define nRF24L01 interrupt flag's
Const Idle_int = &H00                                       'Idle, no interrupt pending
Const Max_rt = &H10                                         'Max #of Tx Retrans Interrupt
Const Tx_ds = &H20                                          'Tx Data Sent Interrupt
Const Rx_dr = &H40                                          'Rx Data Received
'SPI(nRF24L01) commands
Const Read_reg = &H00                                       'Define Read Command To Register
Const Write_reg = &H20                                      'Define Write Command To Register
Const Rd_rx_pload = &H61                                    'Define Rx Payload Register Address
Const Wr_tx_pload = &HA0                                    'Define Tx Payload Register Address
Const Flush_tx = &HE1                                       'Define Flush Tx Register Command
Const Flush_rx = &HE2                                       'Define Flush Rx Register Command
Const Reuse_tx_pl = &HE3                                    'Define Reuse Tx Payload Register Command
Const Nop_comm = &HFF                                       'Define No Operation , Might Be Used To Read Status Register

'---------------------[ SPI(nRF24L01) registers(addresses) ]--------------------
Const Config_nrf = &H00                                     'Config' register address
Const En_aa = &H01                                          'Enable Auto Acknowledgment' register address
Const En_rxaddr = &H02                                      'Enabled RX addresses' register address
Const Setup_aw = &H03                                       'Setup address width' register address
Const Setup_retr = &H04                                     'Setup Auto. Retrans' register address
Const Rf_ch = &H05                                          'RF channel' register address
Const Rf_setup = &H06                                       'RF setup' register address
Const Status = &H07                                         'Status' register address
Const Observe_tx = &H08                                     'Observe TX' register address
Const Cd = &H09                                             'Carrier Detect' register address
Const Rx_addr_p0 = &H0A                                     'RX address pipe0' register address
Const Rx_addr_p1 = &H0B                                     'RX address pipe1' register address
Const Rx_addr_p2 = &H0C                                     'RX address pipe2' register address
Const Rx_addr_p3 = &H0D                                     'RX address pipe3' register address
Const Rx_addr_p4 = &H0E                                     'RX address pipe4' register address
Const Rx_addr_p5 = &H0F                                     'RX address pipe5' register address
Const Tx_addr = &H10                                        'TX address' register address
Const Rx_pw_p0 = &H11                                       'RX payload width, pipe0' register address
Const Rx_pw_p1 = &H12                                       'RX payload width, pipe1' register address
Const Rx_pw_p2 = &H13                                       'RX payload width, pipe2' register address
Const Rx_pw_p3 = &H14                                       'RX payload width, pipe3' register address
Const Rx_pw_p4 = &H15                                       'RX payload width, pipe4' register address
Const Rx_pw_p5 = &H16                                       'RX payload width, pipe5' register address
Const Fifo_status = &H17                                    'FIFO Status Register' register address

'Various
Const True = 1
Const False = 0

'==============================[ Config hardware ]==============================
Config Spi = Hard , Interrupt = Off , Data Order = Msb , Master = Yes , Polarity = Low , Phase = 0 , Clockrate = 4 , Noss = 1
'Software SPI is NOT working with the nRF24L01, use hardware SPI only, but the SS pin must be controlled by our self

Config Pinc.5 = Output                                      'CE pin is output
Config Pinb.2 = Output                                      'SS pin is output
Config Pinc.4 = Input                                       'IRQ pin is input
Config Pinc.3 = Input                                       'TX/RX Device _select

         Ce Alias Portc.5
         Ss Alias Portb.2
        Irq Alias Pinc.4
Txrx_device Alias Pinc.3

Spiinit                                                     'init the spi pins
Set Ce
   Waitms 10                                                'Wait a moment until all hardware is stable
Reset Ce                                                    'Set CE pin low
Reset Ss                                                    'Set SS pin low (CSN pin)

Dim D_bytes(33) As Byte , B_bytes(33) As Byte               'Dim the bytes use for SPI, D_bytes = outgoing  B_bytes = Incoming
Dim Temp As Byte , W As Word
Dim Packet_count As Byte

If Txrx_device = True Then Goto Main_tx                     'Is this the RX or TX device?
'===================================[ Main rx ]=================================
Main_rx:
   Call R_register(status , 1)                              'Read STATUS register

   Print "Rx_device"                                        'Send to terminal who i'm

   Reset Ce                                                 'Set CE low to access the registers

   Gosub Setup_rx                                           'Setup the nRF24L01 for RX
      Waitms 2                                              'Add a delay before going in RX
   Set Ce                                                   'Set nRF20L01 in RX mode

Do                                                          'Main loop for RX
   If Irq = 0 Then                                          'Wait until IRQ occurs, pin becomes low on interrupt
      Reset Ce                                              'Receiver must be disabled before reading pload

      Do                                                    'Loop until all 3 fifo buffers are empty
         Call R_register(rd_rx_pload , 5)                   'Read 5 bytes RX pload register
         Print "Pload  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; _
                              Hex(b_bytes(3)) ; Hex(b_bytes(4)) ; Hex(b_bytes(5))       'Print the pload
         Call R_register(fifo_status , 1)                   'Read FIFO_STATUS
      Loop Until B_bytes(1).0 = True                        'Test or RX_EMPTY bit is true, RX FIFO empty

      D_bytes(1) = Write_reg + Status                       'Reset the RX_DR status bit
      D_bytes(2) = &B01000000                               'Write 1 to RX_DR bit to reset IRQ
      Call W_register(2)

      Set Ce                                                'Enable receiver again
      Waitms 2
   End If
'--Gosub Dump_registers                                        'Unremark me for debugging
Loop
Return

'=====================================[ Main tx ]===============================
Main_tx:
   Print "TX_device"                                        'Send to terminal who i'm

   D_bytes(1) = Flush_tx                                    'Flush the TX_fifo buffer
   Call W_register(1)

   D_bytes(1) = Write_reg + Status                          'Reset the IRQ bits
   D_bytes(2) = &B_0011_0000
   Call W_register(2)

   Do                                                       'Main loop for TX
      Incr Packet_count                                     'Increase the send packet counter, for test only
      If Packet_count > 254 Then Packet_count = 0
      Gosub Setup_tx                                        'Setup the nRF240L01 for TX

      D_bytes(1) = Wr_tx_pload                              'Put 5 bytes in the TX pload buffer
      D_bytes(2) = &HAA                                     'Byte 1
      D_bytes(3) = &HBB                                     'Byte 2
      D_bytes(4) = &HCC                                     'Byte 3
      D_bytes(5) = &H11                                     'Byte 4
      D_bytes(6) = Packet_count                             'Byte 5 will be increase every loop
      Call W_register(6)                                    'Write 6 bytes to register

         Waitms 2
      Set Ce                                                'Set CE for a short moment to transmit the fifo buffer
         Waitms 1                                           '
      Reset Ce                                              '
         Waitms 100                                         'Some delay to read the output on the terminal, line can be removed for max. speed
      W = 0                                                 'Counter for time out

      Do
      If Irq = 0 Then
         Call R_register(status , 1)
         Temp = B_bytes(1) And &B01110000                   'Mask the IRQ bits out the status byte

         Select Case Temp                                   'Which IRQ occurs

            Case Max_rt                                     'MAX_RT
               Print "Maximum number of TX retries, Flussing the TX buffer now !"
               D_bytes(1) = Flush_tx                        'Flush the TX buffer
               Call W_register(1)
               D_bytes(1) = Write_reg + Status
               D_bytes(2) = &B00010000                      'Clear the MAX_RT IRQ bit
               Call W_register(2)
               Exit Do

            Case Tx_ds                                      'TX_DS
               Print "Packet " ; Packet_count ; " send and ACK received."
               D_bytes(1) = Write_reg + Status
               D_bytes(2) = &B00100000                      'Clear the TX_DS IRQ bit
               Call W_register(2)
               Exit Do

            Case Else                                       'Other IRQ ??
               Print "Other irq " ; Bin(temp)
               D_bytes(1) = Flush_tx                        'Flush the TX buffer
               Call W_register(1)
               D_bytes(1) = Write_reg + Status
               D_bytes(2) = &B00110000                      'Clear both MAX_RT, TX_DS bits
               Call W_register(2)
         End Select
      End If

      Waitms 1                                              'Time out waiting for IRQ 1ms * 100
      Incr W                                                'Increment W

      If W > 100 Then                                       'Waited for 100ms
         Print "No irq response from RF20L01 within 100ms"
         Exit Do                                            'Exit the wait loop
      End If
   Loop
Loop

Return

'-------------------------------[ Write register ]------------------------------
Sub W_register(byval C_bytes As Byte)                       'Write register with SPI
   Reset Ss                                                 'Manual control SS pin, set SS low before shifting out the bytes
      Spiout D_bytes(1) , C_bytes                           'Shiftout the data bytes trough SPI , C_bytes is the amount bytes to be written
   Set Ss                                                   'Set SS high
End Sub

'-------------------------------[ Read register ]-------------------------------
Sub R_register(byval Command As Byte , Byval C_bytes As Byte) As Byte       'C_bytes = Count_bytes, number off bytes to be read
   Reset Ss                                                 'Manual controle SS pin, set low before shifting in/out the bytes
      Spiout Command , 1                                    'First shiftout the register to be read
      Spiin B_bytes(1) , C_bytes                            'Read back the bytes from SPI sended by nRF24L01
   Set Ss                                                   'Set SS back to high level
End Sub

'----------------------------[ Setup RX ]---------------------------------------
Setup_rx:                                                   'Setup for RX

D_bytes(1) = Write_reg + Rx_addr_p0                         'RX adress for pipe0
D_bytes(2) = &H34
D_bytes(3) = &H43
D_bytes(4) = &H10
D_bytes(5) = &H10
D_bytes(6) = &H01
   Call W_register(6)                                       'Send 6 bytes to SPI

D_bytes(1) = Write_reg + En_aa                              'Enable auto ACK for pipe0
D_bytes(2) = &H01
   Call W_register(2)

D_bytes(1) = Write_reg + En_rxaddr                          'Enable RX adress for pipe0
D_bytes(2) = &H01
   Call W_register(2)

D_bytes(1) = Write_reg + Rf_ch                              'Set RF channel
D_bytes(2) = 40
   Call W_register(2)

D_bytes(1) = Write_reg + Rx_pw_p0                           'Set RX pload width for pipe0
D_bytes(2) = 5
   Call W_register(2)

D_bytes(1) = Write_reg + Rf_setup                           'Setup RF-> Output power 0dbm, datarate 2Mbps and LNA gain on
D_bytes(2) = &H0F
   Call W_register(2)

D_bytes(1) = Write_reg + Config_nrf                         'Setup CONFIG-> PRX=1(RX_device), PWR_UP=1, CRC 2bytes, Enable CRC
D_bytes(2) = &H0F
   Call W_register(2)
Return
'----------------------------[ Setup TX ]---------------------------------------
Setup_tx:                                                   'Setup for TX

D_bytes(1) = Write_reg + Tx_addr                            'TX adress
D_bytes(2) = &H34
D_bytes(3) = &H43
D_bytes(4) = &H10
D_bytes(5) = &H10
D_bytes(6) = &H01
   Call W_register(6)

D_bytes(1) = Write_reg + Rx_addr_p0                         'RX adress for pipe0
D_bytes(2) = &H34
D_bytes(3) = &H43
D_bytes(4) = &H10
D_bytes(5) = &H10
D_bytes(6) = &H01
   Call W_register(6)

D_bytes(1) = Write_reg + En_aa                              'Enable auto ACK for pipe0
D_bytes(2) = &H01
   Call W_register(2)

D_bytes(1) = Write_reg + En_rxaddr                          'Enable RX adress for pipe0
D_bytes(2) = &H01
   Call W_register(2)

D_bytes(1) = Write_reg + Rf_ch                              'Set RF channel
D_bytes(2) = 40
   Call W_register(2)

D_bytes(1) = Write_reg + Rf_setup                           'Setup RF-> Output power 0dbm, datarate 2Mbps and LNA gain on
D_bytes(2) = &H0F
   Call W_register(2)

D_bytes(1) = Write_reg + Config_nrf                         'Setup CONFIG-> PRX=0(TX_device), PWR_UP=1, CRC 2bytes, Enable CRC
D_bytes(2) = &H0E
   Call W_register(2)
Return
'---------------------------[ Dump Registers ]----------------------------------
Dump_registers:                                             'Dumps all nRF24L01 registers to the terminal, handy for debugging

Print "* Dump nRF24L01 Registers *"

Call R_register(config_nrf , 1)
Print "CONFIG      : " ; Bin(b_bytes(1))

Call R_register(en_aa , 1)
Print "EN_AA       : " ; Bin(b_bytes(1))

Call R_register(en_rxaddr , 1)
Print "EN_RXADDR   : " ; Bin(b_bytes(1))

Call R_register(setup_aw , 1)
Print "SETUP_AW    : " ; Bin(b_bytes(1))

Call R_register(setup_retr , 1)
Print "SETUP_RETR  : " ; Bin(b_bytes(1))

Call R_register(rf_ch , 1)
Print "RF_CH       : " ; B_bytes(1)

Call R_register(rf_setup , 1)
Print "RF_SETUP    : " ; Bin(b_bytes(1))

Call R_register(status , 1)
Print "STATUS      : " ; Bin(b_bytes(1))

Call R_register(observe_tx , 1)
Print "OBSERVE_TX  : " ; Bin(b_bytes(1))

Call R_register(cd , 1)
Print "CD          : " ; Bin(b_bytes(1))

Call R_register(rx_addr_p0 , 5)
Print "RX_ADDR_P0  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_addr_p1 , 5)
Print "RX_ADDR_P1  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_addr_p2 , 5)
Print "RX_ADDR_P2  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_addr_p3 , 5)
Print "RX_ADDR_P3  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_addr_p4 , 5)
Print "RX_ADDR_P4  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_addr_p5 , 5)
Print "RX_ADDR_P5  : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(tx_addr , 5)
Print "TX_ADDR     : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p0 , 5)
Print "RX_PW_P0    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p1 , 5)
Print "RX_PW_P1    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p2 , 5)
Print "RX_PW_P2    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p3 , 5)
Print "RX_PW_P3    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p4 , 5)
Print "RX_PW_P4    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(rx_pw_p5 , 5)
Print "RX_PW_P5    : " ; Hex(b_bytes(1)) ; Hex(b_bytes(2)) ; Hex(b_bytes(3)) ; _
                           Hex(b_bytes(4)) ; Hex(b_bytes(5))

Call R_register(fifo_status , 1)
Print "FIFO_STATUS : " ; Bin(b_bytes(1))
Return