Has anyone successfully used lora.nvram_save() and restore?

[Harish kumar]

Hi Everyone !
I am confused with using lora.nvram_save and restore. I am using in my program but I am not sure where and how to use. Can someone guide me in this. I will put my code here.
Thank you in Advance.

from network import LoRa
import socket
import time
import ubinascii
store =["26012FF8", "26012FF7", "f82f0126" ]
#creating a OTAA connection
app_eui = ubinascii.unhexlify('0004A30B00000000')
app_key = ubinascii.unhexlify('DE71C5CA71E05F92FE3B000000000')

Join a network with OTAA

lora.join(activation=LoRa.OTAA, auth=(app_eui, app_key), timeout=0)

#wait until the module to join
while not lora.has_joined():
time.sleep(2.5)
print('Not yet joined...')

#create a lora socket
s = socket.socket(socket.AF_LORA, socket.SOCK_RAW)

#set lorawan datarate
s.setsockopt(socket.SOL_LORA, socket.SO_DR, 5)

#make the socket blocking
s.setblocking(True)

time.sleep(3000)
s.send(bytes([0x01, 0x02, 0x03]))

time.sleep(3000)
s.send(bytes([0x01, 0x02, 0x03]))

lora.nvram_save()

while True:

lora = LoRa(mode=LoRa.LORA, region=LoRa.EU868, sf = 7, frequency = 868500000)

# create a raw LoRa socket
s = socket.socket(socket.AF_LORA, socket.SOCK_RAW)
s.setblocking(True)
rx_data = s.recv(64)
dev_addr = rx_data[1:5]
print("Dev-Addr: ", binascii.hexlify(dev_addr))
x = 0
for x in range(0, 3):
    if(binascii.unhexlify(store[x]) == dev_addr):
        print('OK') 
        # get any data received...
        #rx_data = s.recv(64)
        print(rx_data)
        # sending data to server with sf = 12
        lora = LoRa(mode=LoRa.LORAWAN, region=LoRa.EU868,  sf = 12)        
        # send some data
        s.send(rx_data)
        
        print('data sent')
    else:
        print('Not OK')

lora = LoRa(mode=LoRa.LORAWAN)
lora.nvram_restore()

#join a network using OTAA
lora.join(activation=LoRa.OTAA, auth=(app_eui, app_key), timeout=0)

#create a lora socket
s = socket.socket(socket.AF_LORA, socket.SOCK_RAW)

#doing uplink
s.send(bytes([0x01, 0x02, 0x03]))

#doing downlink
data = s.recv(64)
first4 = data[0:4]
store.append(first4)
second4 = data[5:9]
store.append(second4)
print(data)

And here, I am trying to save my OTAA connection and at last I am restoring those keys to do uplink again to get some downlinks.

[Harish kumar]

@jcaron oh thank you. I will do that. And I need a small help from you. In this code, I am trying to start my downlink once in a day. So I am using this code.

import time

a = time.localtime()

hour = a.tm_hour
minutes = a.tm_min

if hour == 10 and minutes == 40:
print('{0}:{1}'.format(hour, minutes))

But it's not working properly. Do I have to change some conditions ?

[jcaron]

@harish-kumar you only need to use nvram_save/restore if you use deep sleep (or cut power to the LoPy), which is not the case here.

Just keep the same Lora object and socket and don’t join again...