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V0.3 BETA

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BLavery 2014-11-05 21:34:16 +10:00
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README.md Normal file
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lib_nrf24
=========
Python2/3 library for NRF24L01+ Transceivers
V0.3 beta
For Raspberry Pi and virtual-GPIO.
NRF24: strictly 3.3V supply!! Although logic pins are 5V tolerant.
This is BETA only so far.
Everything has worked earlier, send, receive, including two RF24 on one host, and including RPI, virtual-GPIO and regular arduino sketch, all talking to each other.
But recent testing has been only LIBRARY plus "example-nrf24-pair.py" on virtual-GPIO, so other parts are yet to be re-verified.

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example-nrf24-pair.py Normal file
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#!/usr/bin/python
#
# Example program to send packets between 2 NRF24L01+ radios
#
# Demonstrates: 2 x NRF24 radios both operating from SPI on one virt-GPIO, doing 2-way radio data transfer
# Dynamic payload size both ways (to 32 bytes).
# "Auto-Ack" mode, with "ack-payload" carrying the return data.
# Forward payload and return ack-payload data content is rather arbitrary, but is identifiable.
# (Single PTX-PRX link is demonstrated, although PRX has 6-channel capacity.)
# Setup: 2 x NRF24L01+ (each with 5V to 3.3V "adapter plate") (total eBay cost under $5, "8 pin" types)
# Radio1 in PTX (master) mode, radio2 in PRX (slave/server) mode.
# Pins: Radio1 Arduino pin9 as NRF24-CSN (spi CE), Tie RF24-CE to HIGH (+3 or +5)
# Radio2 Arduino pin10 as NRF24-CSN, Tie RF24-CE to HIGH (+3 or +5)
# (VirtGPIO/arduino uses notation "CE" differently from NRF24 usage!)
# Both radios: Arduino pin11 = MOSI, pin12 = MISO, pin13 = SCLK
# Note: NRF24 power MUST be 3.3V, NOT 5v. (Its data pins may operate at 3.3V or 5V.)
# Optionally, a LED on pin6, as switched-across "activity Led".
import virtGPIO as GPIO
from lib_nrf24 import NRF24
import time
pipes = [[0xe7, 0xe7, 0xe7, 0xe7, 0xe7], [0xc2, 0xc2, 0xc2, 0xc2, 0xc2]]
# Comment re multiple SPIDEV devices:
# Official spidev documentation is sketchy. Implementation in virtGPIO allows multiple SpiDev() objects.
# This may not work on RPi? Probably RPi uses alternating open() / xfer2() /close() within one SpiDev() object???
# On virtGPIO each of multiple SpiDev() stores its own mode and cePin. Multiple RF24 used here becomes easy.
# This issue affects only using MULTIPLE Spi devices.
##################################################################
# SET UP RADIO1 - PTX
radio1 = NRF24(GPIO, GPIO.SpiDev())
radio1.begin(9) # SPI-CE=RF24-CSN=pin9, no RF24-CE pin
time.sleep(1)
radio1.setRetries(15,15)
radio1.setPayloadSize(32)
radio1.setChannel(0x62)
radio1.setDataRate(NRF24.BR_2MBPS)
radio1.setPALevel(NRF24.PA_MIN)
radio1.setAutoAck(True)
radio1.enableDynamicPayloads()
radio1.enableAckPayload()
radio1.openWritingPipe(pipes[1])
radio1.openReadingPipe(1, pipes[0])
if not radio1.isPVariant():
# If radio configures correctly, we confirmed a "plus" (ie "variant") nrf24l01+
# Else print diagnostic stuff & exit.
radio1.printDetails()
# (or we could always just print details anyway, even on good setup, for debugging)
print ("NRF24L01+ not found.")
exit()
##################################################################
# AND THEN RADIO2 - PRX - VIRTUALLY IDENTICAL !
radio2 = NRF24(GPIO, GPIO.SpiDev())
radio2.begin(10) # SPI-CE=RF24-CSN=pin10, no RF24-CE pin
time.sleep(1)
radio2.setRetries(15,15)
radio2.setPayloadSize(32)
radio2.setChannel(0x62)
radio2.setDataRate(NRF24.BR_2MBPS)
radio2.setPALevel(NRF24.PA_MIN)
radio2.setAutoAck(True)
radio2.enableDynamicPayloads()
radio2.enableAckPayload()
radio2.openWritingPipe(pipes[0])
radio2.openReadingPipe(1, pipes[1])
radio2.startListening()
if not radio2.isPVariant():
radio2.stopListening()
radio2.printDetails()
print ("NRF24L01+ not found.")
exit()
##################################################################
c1 = 1
def serviceRadio1():
# Let's deal with PTX - radio1:
print ("TX:")
global c1
global radio1
buf = ['H', 'E', 'L', 'O',(c1 & 255)] # something to recognise at other end
c1 += 1
# send a packet to receiver
radio1.write(buf)
# RF24 handles all timeouts, retries and ACKs and ACK-payload
# So the call to radio.write() only returns after ack and its payload have finished
print ("\033[31;1mPTX Sent:\033[0m"),
print (buf)
# did a payload come back with the ACK?
if radio1.isAckPayloadAvailable():
pl_buffer=[]
radio1.read(pl_buffer, radio1.getDynamicPayloadSize())
print ("\033[31;1mPTX Received back:\033[0m"),
print (pl_buffer)
else:
print ("PTX Received: Ack only, no payload")
##################################################################
c2 = 1
def serviceRadio2():
# Now deal separately with PRX - radio 2
print ("RX?")
global c2
global radio2
akpl_buf = [(c2& 255),1, 2, 3,4,5,6,7,8,9,0,1, 2, 3,4,5,6,7,8] # We should see this returned to PTX
pipe = [0]
if not radio2.available(pipe):
return
recv_buffer = []
radio2.read(recv_buffer, radio2.getDynamicPayloadSize())
print ("\033[32;1mPRX Received:\033[0m") ,
print (recv_buffer)
c2 += 1
if (c2&1) == 0: # alternate times - so we can see difference beteeen ack-payload and no ack-payload
radio2.writeAckPayload(1, akpl_buf, len(akpl_buf))
print ("PRX Loaded payload reply:"),
print (akpl_buf)
else:
print ("PRX: (No return payload)")
##################################################################
# We could experiment with differing payload lengths above, up to max 32 bytes each way.
c=0
while True:
c += 1
print ("Loop %d" % c),
if not (c % 3): # only once per x loops
serviceRadio1() # send something
time.sleep(0.01)
else:
serviceRadio2() # has it arrived? (if so, maybe send return data)
time.sleep(2) # 1 sec per loop

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#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Example program to receive packets from the radio link
#
import virtGPIO as GPIO
from lib_nrf24 import NRF24
import time
pipes = [[0xe7, 0xe7, 0xe7, 0xe7, 0xe7], [0xc2, 0xc2, 0xc2, 0xc2, 0xc2]]
radio2 = NRF24(GPIO, GPIO.SpiDev())
radio2.begin(9, 7)
radio2.setRetries(15,15)
radio2.setPayloadSize(32)
radio2.setChannel(0x60)
radio2.setDataRate(NRF24.BR_2MBPS)
radio2.setPALevel(NRF24.PA_MIN)
radio2.setAutoAck(True)
radio2.enableDynamicPayloads()
radio2.enableAckPayload()
radio2.openWritingPipe(pipes[0])
radio2.openReadingPipe(1, pipes[1])
radio2.startListening()
radio2.stopListening()
radio2.printDetails()
radio2.startListening()
c=1
while True:
akpl_buf = [c,1, 2, 3,4,5,6,7,8,9,0,1, 2, 3,4,5,6,7,8]
pipe = [0]
while not radio2.available(pipe):
time.sleep(10000/1000000.0)
recv_buffer = []
radio2.read(recv_buffer, radio2.getDynamicPayloadSize())
print ("Received:") ,
print (recv_buffer)
c = c + 1
if (c&1) == 0:
radio2.writeAckPayload(1, akpl_buf, len(akpl_buf))
print ("Loaded payload reply:"),
print (akpl_buf)
else:
print ("(No return payload)")

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example-nrf24-send.py Normal file
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#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# Example program to send packets to the radio link
#
import virtGPIO as GPIO
from lib_nrf24 import NRF24
import time
pipes = [[0xe7, 0xe7, 0xe7, 0xe7, 0xe7], [0xc2, 0xc2, 0xc2, 0xc2, 0xc2]]
radio = NRF24(GPIO, GPIO.SpiDev())
radio.begin(10, 8) #Set spi-ce pin10, and rf24-CE pin 8
time.sleep(1)
radio.setRetries(15,15)
radio.setPayloadSize(32)
radio.setChannel(0x60)
radio.setDataRate(NRF24.BR_2MBPS)
radio.setPALevel(NRF24.PA_MIN)
radio.setAutoAck(True)
radio.enableDynamicPayloads()
radio.enableAckPayload()
radio.openWritingPipe(pipes[1])
radio.openReadingPipe(1, pipes[0])
radio.printDetails()
c=1
while True:
buf = ['H', 'E', 'L', 'O',c]
c = (c + 1) & 255
# send a packet to receiver
radio.write(buf)
print ("Sent:"),
print (buf)
# did it return with a payload?
if radio.isAckPayloadAvailable():
pl_buffer=[]
radio.read(pl_buffer, radio.getDynamicPayloadSize())
print ("Received back:"),
print (pl_buffer)
else:
print ("Received: Ack only, no payload")
time.sleep(10)

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#!/usr/bin/python
# -*- coding: utf-8 -*-
#
# This file lib_nrf24.py is a slightly tweaked version of Barraca's "pynrf24".
# So this is my tweak for Raspberry Pi and "Virtual GPIO" ...
# ... of Barraca's port to BeagleBone python ... (Joao Paulo Barraca <jpbarraca@gmail.com>)
# ... of maniacbug's NRF24L01 C++ library for Arduino.
# Brian Lavery Oct 2014
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
import sys
import time
if __name__ == '__main__':
print (sys.argv[0], 'is an importable module:')
print ("... from", sys.argv[0], "import lib_nrf24")
print ("")
exit()
def _BV(x):
return 1 << x
class NRF24:
MAX_CHANNEL = 127
MAX_PAYLOAD_SIZE = 32
# PA Levels
PA_MIN = 0
PA_LOW = 1
PA_HIGH = 2
PA_MAX = 3
PA_ERROR = 4
# Bit rates
BR_1MBPS = 0
BR_2MBPS = 1
BR_250KBPS = 2
# CRC
CRC_DISABLED = 0
CRC_8 = 1
CRC_16 = 2
CRC_ENABLED = 3
# Registers
CONFIG = 0x00
EN_AA = 0x01
EN_RXADDR = 0x02
SETUP_AW = 0x03
SETUP_RETR = 0x04
RF_CH = 0x05
RF_SETUP = 0x06
STATUS = 0x07
OBSERVE_TX = 0x08
CD = 0x09
RX_ADDR_P0 = 0x0A
RX_ADDR_P1 = 0x0B
RX_ADDR_P2 = 0x0C
RX_ADDR_P3 = 0x0D
RX_ADDR_P4 = 0x0E
RX_ADDR_P5 = 0x0F
TX_ADDR = 0x10
RX_PW_P0 = 0x11
RX_PW_P1 = 0x12
RX_PW_P2 = 0x13
RX_PW_P3 = 0x14
RX_PW_P4 = 0x15
RX_PW_P5 = 0x16
FIFO_STATUS = 0x17
DYNPD = 0x1C
FEATURE = 0x1D
# Bit Mnemonics */
MASK_RX_DR = 6
MASK_TX_DS = 5
MASK_MAX_RT = 4
EN_CRC = 3
CRCO = 2
PWR_UP = 1
PRIM_RX = 0
ENAA_P5 = 5
ENAA_P4 = 4
ENAA_P3 = 3
ENAA_P2 = 2
ENAA_P1 = 1
ENAA_P0 = 0
ERX_P5 = 5
ERX_P4 = 4
ERX_P3 = 3
ERX_P2 = 2
ERX_P1 = 1
ERX_P0 = 0
AW = 0
ARD = 4
ARC = 0
PLL_LOCK = 4
RF_DR = 3
RF_PWR = 6
RX_DR = 6
TX_DS = 5
MAX_RT = 4
RX_P_NO = 1
TX_FULL = 0
PLOS_CNT = 4
ARC_CNT = 0
TX_REUSE = 6
FIFO_FULL = 5
TX_EMPTY = 4
RX_FULL = 1
RX_EMPTY = 0
DPL_P5 = 5
DPL_P4 = 4
DPL_P3 = 3
DPL_P2 = 2
DPL_P1 = 1
DPL_P0 = 0
EN_DPL = 2
EN_ACK_PAY = 1
EN_DYN_ACK = 0
# Instruction Mnemonics
R_REGISTER = 0x00
W_REGISTER = 0x20
REGISTER_MASK = 0x1F
ACTIVATE = 0x50
R_RX_PL_WID = 0x60
R_RX_PAYLOAD = 0x61
W_TX_PAYLOAD = 0xA0
W_ACK_PAYLOAD = 0xA8
FLUSH_TX = 0xE1
FLUSH_RX = 0xE2
REUSE_TX_PL = 0xE3
NOP = 0xFF
# Non-P omissions
LNA_HCURR = 0x00
# P model memory Map
RPD = 0x09
# P model bit Mnemonics
RF_DR_LOW = 5
RF_DR_HIGH = 3
RF_PWR_LOW = 1
RF_PWR_HIGH = 2
# Signal Mnemonics
LOW = 0
HIGH = 1
datarate_e_str_P = ["1MBPS", "2MBPS", "250KBPS"]
model_e_str_P = ["nRF24L01", "nRF24l01+"]
crclength_e_str_P = ["Disabled", "8 bits", "16 bits"]
pa_dbm_e_str_P = ["PA_MIN", "PA_LOW", "PA_MED", "PA_HIGH"]
child_pipe = [RX_ADDR_P0, RX_ADDR_P1, RX_ADDR_P2, RX_ADDR_P3, RX_ADDR_P4, RX_ADDR_P5]
child_payload_size = [RX_PW_P0, RX_PW_P1, RX_PW_P2, RX_PW_P3, RX_PW_P4, RX_PW_P5]
child_pipe_enable = [ERX_P0, ERX_P1, ERX_P2, ERX_P3, ERX_P4, ERX_P5]
GPIO = None
spidev = None
def __init__(self, gpio, spidev):
# It should be possible to instantiate multiple objects, with different GPIO / spidev
# EG on Raspberry, one could be RPI GPIO & spidev module, other could be virtual-GPIO
# On rpi, only bus 0 is supported here, not bus 1 of the model B plus
self.GPIO = gpio # the GPIO module
self.spidev = spidev # the spidev object/instance
self.channel = 76
self.data_rate = NRF24.BR_1MBPS
self.wide_band = False # 2Mbs data rate in use?
self.p_variant = False # False for RF24L01 and true for RF24L01P (nrf24l01+)
self.payload_size = 5 #*< Fixed size of payloads
self.ack_payload_available = False #*< Whether there is an ack payload waiting
self.dynamic_payloads_enabled = False #*< Whether dynamic payloads are enabled.
self.ack_payload_length = 5 #*< Dynamic size of pending ack payload.
self.pipe0_reading_address = None #*< Last address set on pipe 0 for reading.
def ce(self, level):
if self.ce_pin == 0:
return
# rf24-CE is optional. Tie to HIGH if not used. (Altho, left floating seems to read HIGH anyway??? - risky!)
# Some RF24 modes may NEED control over CE.
# non-powerdown, fixed PTX or RTX role, dynamic payload size & ack-payload: does NOT need CE.
if level == NRF24.HIGH:
self.GPIO.output(self.ce_pin, self.GPIO.HIGH)
else:
self.GPIO.output(self.ce_pin, self.GPIO.LOW)
return
def read_register(self, reg, blen=1):
buf = [NRF24.R_REGISTER | ( NRF24.REGISTER_MASK & reg )]
for col in range(blen):
buf.append(NRF24.NOP)
resp = self.spidev.xfer2(buf)
if blen == 1:
return resp[1]
return resp[1:blen + 1]
def write_register(self, reg, value, length=-1):
buf = [NRF24.W_REGISTER | ( NRF24.REGISTER_MASK & reg )]
###if isinstance(value, (int, long)): # ng for python3. but value should never be long anyway
if isinstance(value, int):
if length < 0:
length = 1
length = min(4, length)
for i in range(length):
buf.insert(1, int(value & 0xff))
value >>= 8
elif isinstance(value, list):
if length < 0:
length = len(value)
for i in range(min(len(value), length)):
buf.append(int(value[len(value) - i - 1] & 0xff))
else:
raise Exception("Value must be int or list")
return self.spidev.xfer2(buf)[0]
def write_payload(self, buf):
data_len = min(self.payload_size, len(buf))
blank_len = 0
if not self.dynamic_payloads_enabled:
blank_len = self.payload_size - data_len
txbuffer = [NRF24.W_TX_PAYLOAD]
for n in buf:
t = type(n)
if t is str:
txbuffer.append(ord(n))
elif t is int:
txbuffer.append(n)
else:
raise Exception("Only ints and chars are supported: Found " + str(t))
if blank_len != 0:
blank = [0x00 for i in range(blank_len)]
txbuffer.extend(blank)
return self.spidev.xfer2(txbuffer)
def read_payload(self, buf, buf_len=-1):
if buf_len < 0:
buf_len = self.payload_size
data_len = min(self.payload_size, buf_len)
blank_len = 0
if not self.dynamic_payloads_enabled:
blank_len = self.payload_size - data_len
txbuffer = [NRF24.NOP for i in range(0, blank_len + data_len + 1)]
txbuffer[0] = NRF24.R_RX_PAYLOAD
payload = self.spidev.xfer2(txbuffer)
del buf[:]
buf.extend(payload[1:data_len + 1])
return data_len
def flush_rx(self):
return self.spidev.xfer2([NRF24.FLUSH_RX])[0]
def flush_tx(self):
return self.spidev.xfer2([NRF24.FLUSH_TX])[0]
def get_status(self):
return self.spidev.xfer2([NRF24.NOP])[0]
def print_status(self, status):
status_str = "STATUS\t = 0x{0:02x} RX_DR={1:x} TX_DS={2:x} MAX_RT={3:x} RX_P_NO={4:x} TX_FULL={5:x}".format(
status,
1 if status & _BV(NRF24.RX_DR) else 0,
1 if status & _BV(NRF24.TX_DS) else 0,
1 if status & _BV(NRF24.MAX_RT) else 0,
((status >> NRF24.RX_P_NO) & 7),
1 if status & _BV(NRF24.TX_FULL) else 0)
print (status_str)
def print_observe_tx(self, value):
print ("Observe Tx: %02x Lost Pkts: %d Retries: %d" % (value, value >> NRF24.PLOS_CNT, value & 15))
def print_byte_register(self, name, reg, qty=1):
extra_tab = '\t' if len(name) < 8 else 0
print ("%s\t%c =" % (name, extra_tab)),
while qty > 0:
print ("0x%02x" % (self.read_register(reg))),
qty -= 1
reg += 1
print ("")
def print_address_register(self, name, reg, qty=1):
extra_tab = '\t' if len(name) < 8 else 0
print ("%s\t%c =" % (name, extra_tab)),
while qty > 0:
qty -= 1
buf = reversed(self.read_register(reg, 5))
reg += 1
sys.stdout.write(" 0x"),
for i in buf:
sys.stdout.write("%02x" % i)
print ("")
def setChannel(self, channel):
self.channel = min(max(0, channel), NRF24.MAX_CHANNEL)
self.write_register(NRF24.RF_CH, self.channel)
def getChannel(self):
return self.read_register(NRF24.RF_CH)
def setPayloadSize(self, size):
self.payload_size = min(max(size, 1), NRF24.MAX_PAYLOAD_SIZE)
def getPayloadSize(self):
return self.payload_size
def printDetails(self):
self.print_status(self.get_status())
self.print_address_register("RX_ADDR_P0-1", NRF24.RX_ADDR_P0, 2)
self.print_byte_register("RX_ADDR_P2-5", NRF24.RX_ADDR_P2, 4)
self.print_address_register("TX_ADDR", NRF24.TX_ADDR)
self.print_byte_register("RX_PW_P0-6", NRF24.RX_PW_P0, 6)
self.print_byte_register("EN_AA", NRF24.EN_AA)
self.print_byte_register("EN_RXADDR", NRF24.EN_RXADDR)
self.print_byte_register("RF_CH", NRF24.RF_CH)
self.print_byte_register("RF_SETUP", NRF24.RF_SETUP)
self.print_byte_register("CONFIG", NRF24.CONFIG)
self.print_byte_register("DYNPD/FEATURE", NRF24.DYNPD, 2)
#
print ("Data Rate\t = %s" % NRF24.datarate_e_str_P[self.getDataRate()])
print ("Model\t\t = %s" % NRF24.model_e_str_P[self.isPVariant()])
print ("CRC Length\t = %s" % NRF24.crclength_e_str_P[self.getCRCLength()])
print ("PA Power\t = %s" % NRF24.pa_dbm_e_str_P[self.getPALevel()])
def begin(self, csn_pin, ce_pin=0): # csn & ce are RF24 terminology. csn = SPI's CE!
# Initialize SPI bus..
# ce_pin is for the rx=listen or tx=trigger pin on RF24 (they call that ce !!!)
# CE optional (at least in some circumstances, eg fixed PTX PRX roles, no powerdown)
# CE seems to hold itself as (sufficiently) HIGH, but tie HIGH is safer!
self.spidev.open(0, csn_pin)
self.ce_pin = ce_pin
if ce_pin:
self.GPIO.setup(self.ce_pin, self.GPIO.OUT)
time.sleep(5 / 1000000.0)
# Set 1500uS (minimum for 32B payload in ESB@250KBPS) timeouts, to make testing a little easier
# WARNING: If this is ever lowered, either 250KBS mode with AA is broken or maximum packet
# sizes must never be used. See documentation for a more complete explanation.
self.write_register(NRF24.SETUP_RETR, (0b0100 << NRF24.ARD) | 0b1111)
# Restore our default PA level
self.setPALevel(NRF24.PA_MAX)
# Determine if this is a p or non-p RF24 module and then
# reset our data rate back to default value. This works
# because a non-P variant won't allow the data rate to
# be set to 250Kbps.
if self.setDataRate(NRF24.BR_250KBPS):
self.p_variant = True
# Then set the data rate to the slowest (and most reliable) speed supported by all
# hardware.
self.setDataRate(NRF24.BR_1MBPS)
# Initialize CRC and request 2-byte (16bit) CRC
self.setCRCLength(NRF24.CRC_16)
# Disable dynamic payloads, to match dynamic_payloads_enabled setting
self.write_register(NRF24.DYNPD, 0)
# Reset current status
# Notice reset and flush is the last thing we do
self.write_register(NRF24.STATUS, _BV(NRF24.RX_DR) | _BV(NRF24.TX_DS) | _BV(NRF24.MAX_RT))
# Set up default configuration. Callers can always change it later.
# This channel should be universally safe and not bleed over into adjacent
# spectrum.
self.setChannel(self.channel)
# Flush buffers
self.flush_rx()
self.flush_tx()
def end(self):
if self.spidev:
self.spidev.close()
self.spidev = None
def startListening(self):
self.write_register(NRF24.CONFIG, self.read_register(NRF24.CONFIG) | _BV(NRF24.PWR_UP) | _BV(NRF24.PRIM_RX))
self.write_register(NRF24.STATUS, _BV(NRF24.RX_DR) | _BV(NRF24.TX_DS) | _BV(NRF24.MAX_RT))
# Restore the pipe0 address, if exists
if self.pipe0_reading_address:
self.write_register(self.RX_ADDR_P0, self.pipe0_reading_address, 5)
# Go!
self.ce(NRF24.HIGH)
# wait for the radio to come up (130us actually only needed)
time.sleep(130 / 1000000.0)
def stopListening(self):
self.ce(NRF24.LOW)
self.flush_tx()
self.flush_rx()
def powerDown(self):
self.write_register(NRF24.CONFIG, self.read_register(NRF24.CONFIG) & ~_BV(NRF24.PWR_UP))
def powerUp(self):
self.write_register(NRF24.CONFIG, self.read_register(NRF24.CONFIG) | _BV(NRF24.PWR_UP))
time.sleep(150 / 1000000.0)
def write(self, buf):
# Begin the write
self.startWrite(buf)
timeout = self.getMaxTimeout() #s to wait for timeout
sent_at = time.time()
while True:
#status = self.read_register(NRF24.OBSERVE_TX, 1)
status = self.get_status()
if (status & (_BV(NRF24.TX_DS) | _BV(NRF24.MAX_RT))) or (time.time() - sent_at > timeout ):
break
time.sleep(10 / 1000000.0)
#obs = self.read_register(NRF24.OBSERVE_TX)
#self.print_observe_tx(obs)
#self.print_status(status)
# (for debugging)
what = self.whatHappened()
result = what['tx_ok']
if what['tx_fail']:
self.flush_tx(); # bl - dont jam up the fifo
# Handle the ack packet
if what['rx_ready']:
self.ack_payload_length = self.getDynamicPayloadSize()
self.ack_payload_available = True ## bl
return result
def startWrite(self, buf):
# Transmitter power-up
self.write_register(NRF24.CONFIG, (self.read_register(NRF24.CONFIG) | _BV(NRF24.PWR_UP) ) & ~_BV(NRF24.PRIM_RX))
# Send the payload
self.write_payload(buf)
# Allons!
if self.ce_pin:
if self.GPIO.RPI_REVISION > 0:
self.ce(self.GPIO.HIGH)
time.sleep(10 / 1000000.0)
self.ce(self.GPIO.LOW)
else:
# virtGPIO is slower. A 10 uSec pulse is better done with pulseOut():
self.GPIO.pulseOut(self.ce_pin, self.GPIO.HIGH, 10)
def getDynamicPayloadSize(self):
return self.spidev.xfer2([NRF24.R_RX_PL_WID, NRF24.NOP])[1]
def available(self, pipe_num=None):
if not pipe_num:
pipe_num = []
status = self.get_status()
result = False
# Sometimes the radio specifies that there is data in one pipe but
# doesn't set the RX flag...
if status & _BV(NRF24.RX_DR) or (status & 0b00001110 != 0b00001110):
result = True
if result:
# If the caller wants the pipe number, include that
if len(pipe_num) >= 1:
pipe_num[0] = ( status >> NRF24.RX_P_NO ) & 0b00000111
# Clear the status bit
# ??? Should this REALLY be cleared now? Or wait until we
# actually READ the payload?
self.write_register(NRF24.STATUS, _BV(NRF24.RX_DR))
# Handle ack payload receipt
if status & _BV(NRF24.TX_DS):
self.write_register(NRF24.STATUS, _BV(NRF24.TX_DS))
return result
def read(self, buf, buf_len=-1):
# Fetch the payload
self.read_payload(buf, buf_len)
# was this the last of the data available?
return self.read_register(NRF24.FIFO_STATUS) & _BV(NRF24.RX_EMPTY)
def whatHappened(self):
# Read the status & reset the status in one easy call
# Or is that such a good idea?
status = self.write_register(NRF24.STATUS, _BV(NRF24.RX_DR) | _BV(NRF24.TX_DS) | _BV(NRF24.MAX_RT))
# Report to the user what happened
tx_ok = status & _BV(NRF24.TX_DS)
tx_fail = status & _BV(NRF24.MAX_RT)
rx_ready = status & _BV(NRF24.RX_DR)
return {'tx_ok': tx_ok, "tx_fail": tx_fail, "rx_ready": rx_ready}
def openWritingPipe(self, value):
# Note that the NRF24L01(+)
# expects it LSB first.
self.write_register(NRF24.RX_ADDR_P0, value, 5)
self.write_register(NRF24.TX_ADDR, value, 5)
max_payload_size = 32
self.write_register(NRF24.RX_PW_P0, min(self.payload_size, max_payload_size))
def openReadingPipe(self, child, address):
# If this is pipe 0, cache the address. This is needed because
# openWritingPipe() will overwrite the pipe 0 address, so
# startListening() will have to restore it.
if child == 0:
self.pipe0_reading_address = address
if child <= 6:
# For pipes 2-5, only write the LSB
if child < 2:
self.write_register(NRF24.child_pipe[child], address, 5)
else:
self.write_register(NRF24.child_pipe[child], address, 1)
self.write_register(NRF24.child_payload_size[child], self.payload_size)
# Note it would be more efficient to set all of the bits for all open
# pipes at once. However, I thought it would make the calling code
# more simple to do it this way.
self.write_register(NRF24.EN_RXADDR,
self.read_register(NRF24.EN_RXADDR) | _BV(NRF24.child_pipe_enable[child]))
def closeReadingPipe(self, pipe):
self.write_register(NRF24.EN_RXADDR,
self.read_register(EN_RXADDR) & ~_BV(NRF24.child_pipe_enable[pipe]))
def toggle_features(self):
buf = [NRF24.ACTIVATE, 0x73]
self.spidev.xfer2(buf)
def enableDynamicPayloads(self):
# Enable dynamic payload throughout the system
self.write_register(NRF24.FEATURE, self.read_register(NRF24.FEATURE) | _BV(NRF24.EN_DPL))
# If it didn't work, the features are not enabled
if not self.read_register(NRF24.FEATURE):
# So enable them and try again
self.toggle_features()
self.write_register(NRF24.FEATURE, self.read_register(NRF24.FEATURE) | _BV(NRF24.EN_DPL))
# Enable dynamic payload on all pipes
# Not sure the use case of only having dynamic payload on certain
# pipes, so the library does not support it.
self.write_register(NRF24.DYNPD, self.read_register(NRF24.DYNPD) | _BV(NRF24.DPL_P5) | _BV(NRF24.DPL_P4) | _BV(
NRF24.DPL_P3) | _BV(NRF24.DPL_P2) | _BV(NRF24.DPL_P1) | _BV(NRF24.DPL_P0))
self.dynamic_payloads_enabled = True
def enableAckPayload(self):
# enable ack payload and dynamic payload features
self.write_register(NRF24.FEATURE,
self.read_register(NRF24.FEATURE) | _BV(NRF24.EN_ACK_PAY) | _BV(NRF24.EN_DPL))
# If it didn't work, the features are not enabled
if not self.read_register(NRF24.FEATURE):
# So enable them and try again
self.toggle_features()
self.write_register(NRF24.FEATURE,
self.read_register(NRF24.FEATURE) | _BV(NRF24.EN_ACK_PAY) | _BV(NRF24.EN_DPL))
# Enable dynamic payload on pipes 0 & 1
self.write_register(NRF24.DYNPD, self.read_register(NRF24.DYNPD) | _BV(NRF24.DPL_P1) | _BV(NRF24.DPL_P0))
def writeAckPayload(self, pipe, buf, buf_len):
txbuffer = [NRF24.W_ACK_PAYLOAD | ( pipe & 0x7 )]
max_payload_size = 32
data_len = min(buf_len, max_payload_size)
txbuffer.extend(buf[0:data_len])
self.spidev.xfer2(txbuffer)
def isAckPayloadAvailable(self):
result = self.ack_payload_available
self.ack_payload_available = False
return result
def isPVariant(self):
return self.p_variant
def setAutoAck(self, enable):
if enable:
self.write_register(NRF24.EN_AA, 0b111111)
else:
self.write_register(NRF24.EN_AA, 0)
def setAutoAckPipe(self, pipe, enable):
if pipe <= 6:
en_aa = self.read_register(NRF24.EN_AA)
if enable:
en_aa |= _BV(pipe)
else:
en_aa &= ~_BV(pipe)
self.write_register(NRF24.EN_AA, en_aa)
def testCarrier(self):
return self.read_register(NRF24.CD) & 1
def testRPD(self):
return self.read_register(NRF24.RPD) & 1
def setPALevel(self, level):
setup = self.read_register(NRF24.RF_SETUP)
setup &= ~( _BV(NRF24.RF_PWR_LOW) | _BV(NRF24.RF_PWR_HIGH))
# switch uses RAM (evil!)
if level == NRF24.PA_MAX:
setup |= (_BV(NRF24.RF_PWR_LOW) | _BV(NRF24.RF_PWR_HIGH))
elif level == NRF24.PA_HIGH:
setup |= _BV(NRF24.RF_PWR_HIGH)
elif level == NRF24.PA_LOW:
setup |= _BV(NRF24.RF_PWR_LOW)
elif level == NRF24.PA_MIN:
nop = 0
elif level == NRF24.PA_ERROR:
# On error, go to maximum PA
setup |= (_BV(NRF24.RF_PWR_LOW) | _BV(NRF24.RF_PWR_HIGH))
self.write_register(NRF24.RF_SETUP, setup)
def getPALevel(self):
power = self.read_register(NRF24.RF_SETUP) & (_BV(NRF24.RF_PWR_LOW) | _BV(NRF24.RF_PWR_HIGH))
if power == (_BV(NRF24.RF_PWR_LOW) | _BV(NRF24.RF_PWR_HIGH)):
return NRF24.PA_MAX
elif power == _BV(NRF24.RF_PWR_HIGH):
return NRF24.PA_HIGH
elif power == _BV(NRF24.RF_PWR_LOW):
return NRF24.PA_LOW
else:
return NRF24.PA_MIN
def setDataRate(self, speed):
result = False
setup = self.read_register(NRF24.RF_SETUP)
# HIGH and LOW '00' is 1Mbs - our default
self.wide_band = False
setup &= ~(_BV(NRF24.RF_DR_LOW) | _BV(NRF24.RF_DR_HIGH))
if speed == NRF24.BR_250KBPS:
# Must set the RF_DR_LOW to 1 RF_DR_HIGH (used to be RF_DR) is already 0
# Making it '10'.
self.wide_band = False
setup |= _BV(NRF24.RF_DR_LOW)
else:
# Set 2Mbs, RF_DR (RF_DR_HIGH) is set 1
# Making it '01'
if speed == NRF24.BR_2MBPS:
self.wide_band = True
setup |= _BV(NRF24.RF_DR_HIGH)
else:
# 1Mbs
self.wide_band = False
self.write_register(NRF24.RF_SETUP, setup)
# Verify our result
if self.read_register(NRF24.RF_SETUP) == setup:
result = True
else:
self.wide_band = False
return result
def getDataRate(self):
dr = self.read_register(NRF24.RF_SETUP) & (_BV(NRF24.RF_DR_LOW) | _BV(NRF24.RF_DR_HIGH))
# Order matters in our case below
if dr == _BV(NRF24.RF_DR_LOW):
# '10' = 250KBPS
return NRF24.BR_250KBPS
elif dr == _BV(NRF24.RF_DR_HIGH):
# '01' = 2MBPS
return NRF24.BR_2MBPS
else:
# '00' = 1MBPS
return NRF24.BR_1MBPS
def setCRCLength(self, length):
config = self.read_register(NRF24.CONFIG) & ~( _BV(NRF24.CRC_16) | _BV(NRF24.CRC_ENABLED))
if length == NRF24.CRC_DISABLED:
# Do nothing, we turned it off above.
self.write_register(NRF24.CONFIG, config)
return
elif length == NRF24.CRC_8:
config |= _BV(NRF24.CRC_ENABLED)
config |= _BV(NRF24.CRC_8)
else:
config |= _BV(NRF24.CRC_ENABLED)
config |= _BV(NRF24.CRC_16)
self.write_register(NRF24.CONFIG, config)
def getCRCLength(self):
result = NRF24.CRC_DISABLED
config = self.read_register(NRF24.CONFIG) & ( _BV(NRF24.CRCO) | _BV(NRF24.EN_CRC))
if config & _BV(NRF24.EN_CRC):
if config & _BV(NRF24.CRCO):
result = NRF24.CRC_16
else:
result = NRF24.CRC_8
return result
def disableCRC(self):
disable = self.read_register(NRF24.CONFIG) & ~_BV(NRF24.EN_CRC)
self.write_register(NRF24.CONFIG, disable)
def setRetries(self, delay, count):
# see specs. Delay code below 5 can conflict with some ACK lengths
# and count should be set = 0 for non-ACK modes
self.write_register(NRF24.SETUP_RETR, (delay & 0xf) << NRF24.ARD | (count & 0xf))
def getRetries(self):
return self.read_register(NRF24.SETUP_RETR)
def getMaxTimeout(self): # seconds
retries = self.getRetries()
tout = (((250+(250*((retries& 0xf0)>>4 ))) * (retries & 0x0f)) / 1000000.0 * 2) + 0.008
# Fudged up to about double Barraca's calculation
# Was too short & was timeing out wrongly. BL
return tout