cat-tracker/src/receive.py
2025-04-11 18:39:49 -07:00

118 lines
3.3 KiB
Python

from .util import sleep, get_addr, digital_read, GDO0_PIN, GDO2_PIN, debug, delay
import time
from .common import strobe, read_register
SIDLE = get_addr('SIDLE')
SFRX = get_addr('SFRX')
SRX = get_addr('SRX')
RXFIFO = get_addr('RXFIFO')
RSSI = get_addr('RSSI')
def print_packet(spi, packet_length):
for i in range(packet_length):
print(f", byte: {0}: 0x{1}", i, read_register(spi, RXFIFO))
#TODO
def save_packet():
print()
def get_rssi_from_pkt(packet):
if len(packet) < 2:
raise ValueError("Packet too short to contain RSSI and status bytes.")
rssi_raw = packet[-2] # Second-to-last byte is RSSI
return rssi_raw
def get_rssi_from_reg(spi):
return read_register(spi, RSSI)
def get_signal_strength_rssi_raw(rssi_raw):
if rssi_raw >= 128:
rssi_dec = rssi_raw - 256
else:
rssi_dec = rssi_raw
return rssi_dec / 2.0 - 74 # According to CC2500 datasheet
def flush_rx(spi):
# Make sure that the radio is in IDLE state before flushing the FIFO
# (Unless RXOFF_MODE has been changed, the radio should be in IDLE state at this point)
delay(10)
strobe(spi, SIDLE)
delay(10)
# Flush RX FIFO
strobe(spi, SFRX)
delay(10)
def rx_data_rf(spi):
strobe(spi, SRX)
gdo2_state = False
count = 0
strength = 0
while(gdo2_state == False):
gdo2_state = digital_read(GDO2_PIN)
delay(1)
count = count+1
if count > 1000:
flush_rx(spi)
# print("ERR NO DATA")
return
while(gdo2_state == True):
gdo2_state = digital_read(GDO2_PIN)
delay(100)
packet_length: int = read_register(spi, RXFIFO)
# print("Packet Length {0}".format(packet_length))
packet: list = [read_register(spi, RXFIFO) for _ in range(packet_length)]
rssi_raw = get_rssi_from_pkt(packet)
strength = get_signal_strength_rssi_raw(rssi_raw)
print("Length: {0} bytes\t Signal: {1} dBm".format(packet_length, strength) )
# Make sure that the radio is in IDLE state before flushing the FIFO
# (Unless RXOFF_MODE has been changed, the radio should be in IDLE state at this point)
strobe(spi, SIDLE)
# Flush RX FIFO
strobe(spi, SFRX)
# def burst_read(spi, addr, length):
# """Read multiple bytes"""
# READ_SINGLE = get_addr("READ_SINGLE")
# READ_BURST = get_addr("READ_BURST")
# return spi.xfer2([addr | READ_SINGLE | READ_BURST] + [0x00] * length)
# def read_fifo(spi):
# # Burst read RX FIFO
# READ_BURST = get_addr("READ_BURST")
# RXFIFO = get_addr("RXFIFO")
# fifo = spi.xfer2([RXFIFO | READ_BURST] + [0x00]*64) # Max 64 bytes
# return fifo[1:]
# def receive_packet(spi):
# SFRX = get_addr("SFRX")
# RXBYTES = get_addr("RXBYTES")
# SRX = get_addr("SRX")
# # Flush RX FIFO
# strobe(spi, SFRX)
# time.sleep(0.5) # 1 ms delay to allow flush
# # Go into RX mode
# strobe(spi, SRX)
# # Wait for data (use GDO0 in real app)
# sleep(0.5)
# # Check RXBYTES
# timeout = time.time() + 2 # 2-second timeout
# while time.time() < timeout:
# rx_bytes = read_register(spi, RXBYTES) & 0x7F
# if rx_bytes > 0:
# data = read_fifo(spi)
# print(f"Received: {data}")
# return data
# time.sleep(0.01)
# print("Timeout: no data received.")