Lora directory help

[kjm1102]

I'm using TTGO esp32 with onboard lora that I setup with

from machine import Pin,SoftSPI,I2C,SoftI2C; from sx127x import SX127x
cnfg={'miso':19, 'mosi':27, 'ss':18, 'sck':5, 'dio_0':26, 'reset':14, 'led':25}
loracnfg={'frequency':9205E5, 'tx_power_level':14, 'signal_bandwidth':125E3, 'spreading_factor': 12, 'coding_rate':5, 'preamble_length':8, 'implicit_header':0, 'sync_word':0x12, 'enable_CRC':0, 'invert_IQ':0}
spi=SoftSPI(baudrate=10000000, polarity=0, phase=0, bits=8, firstbit=SoftSPI.MSB, sck=Pin(cnfg['sck'],Pin.OUT,Pin.PULL_DOWN), mosi=Pin(cnfg['mosi'],Pin.OUT,Pin.PULL_UP), miso=Pin(cnfg['miso'],Pin.IN,Pin.PULL_UP))
lora=SX127x(spi, pins=cnfg, parameters=loracnfg)

so far so good. But when I go looking for some commands that might be useful sometimes I get

>>> dir('lora')
['__class__', 'count', 'endswith', 'find', 'format', 'index', 'isalpha', 'isdigit', 'islower', 'isspace', 'isupper', 'join', 'lower', 'lstrip', 'replace', 'rfind', 'rindex', 'rsplit', 'rstrip', 'split', 'startswith', 'strip', 'upper', 'center', 'encode', 'partition', 'rpartition', 'splitlines']

but other times I get

>>> dir(lora)
['__class__', '__init__', '__module__', '__qualname__', 'write', '__dict__', 'sleep', 'default_parameters', 'enable_CRC', 'invert_IQ', '_spi', '_pins', '_parameters', '_lock', '_pin_rx_done', '_pin_ss', '_led_status', 'read_register', 'set_frequency', 'set_signal_bandwidth', 'write_register', 'set_tx_power', '_implicit_header_mode', 'implicit_header_mode', 'set_spreading_factor', 'set_coding_rate', 'set_preamble_length', 'set_sync_word', 'standby', 'begin_packet', 'end_packet', 'collect_garbage', 'set_lock', 'println', 'get_irq_flags', 'packet_rssi', '_frequency', 'packet_snr', '_tx_power_level', 'set_channel', 'dump_registers', 'receive', 'on_receive', 'handle_on_receive', 'read_payload', 'received_packet', 'transfer', 'blink_led']

Of the two the first one seems dodgy

>>> lora.count()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'SX127x' object has no attribute 'count'

I can't figure out why the 2 different responses as there seems to be only one sx127x

>>> import os; os.listdir(); os.listdir('lib')
['boot.py', 'lib']
['ssd1306.py', 'sx127x.py']

[jimmo]

>>> dir('lora')

@kjm1102 This is doing a dir on the literal string "lora". You mean dir(lora) (as you do in the second example). (Maybe you're confused by help("modules") which is a special case for listing the installed modules).

[davefes]

This is where CAD shines, as a device will detect ongoing transmissions before sending its packet.

Sounds like a listen before transmit feature. I played with RM22B chips years ago, but a LoRa beginner.

[davefes]

https://www.thethingsnetwork.org/forum/t/channel-activity-detection-cad-implementation-of-lora/13373?page=2

[kjm1102]

You don't happen to know a document that explains the difference between lora.on_receive & lora.handle_on_receive do you?

[davefes]

Provide a link to the code you are using. I don't see lora.handle_on_receive in Sandeep's code. In Wei's code onReceive() looks like it is used to generate an interrupt ... when the receive process is finished? I think we need to generate an interrupt when you have got a preamble, to wake-up the ESP32 and proceed.

[kjm1102]

I went for the sx127x library at https://github.com/lemariva/uPyLoRaWAN Dave. I Use it because the same guy had done a pretty good job with the esp32 camera board lib. I'll put all my other posts on https://github.com/orgs/micropython/discussions/11515 so our lora chat is all in one place.