Hi, I try to connect Orangepi lite to SIM800l module. I don't have any response on AT commands. I checked the module with Arduino and it works. So I connected Arduino and Orangepi and I can send messages from Arduino to Orangepi, but I can't get any message from Orangepi to Arduino. 

 

1, On Orangepi I allowed UART3 via editing /boot/script.bin

[uart3]
uart_used = 1
uart_port = 3
uart_type = 4
uart_tx = port:PA13<3><1><default><default>
uart_rx = port:PA14<3><1><default><default>
uart_rts = port:PA15<3><1><default><default>
uart_cts = port:PA16<3><1><default><default>

2, I didn't do anything with GPIO definitions, because I didn't find any such pin definitions in the /boot/script.bin.

3, The physical connection of pins (rx->tx, tx->rx) should be fine. I tried to swith them either. 

4, For reading the port I use this simple script..

import serial

serport = serial.Serial("/dev/ttyS3", 9600, timeout=1)
while True:
    while serport.inWaiting() > 0:
        c = serport.read()
        print(c)

As I've already mentioned, it can read messages from Arduino serial monitor.

5, For writing to the port I use this one...

import serial

serport = serial.Serial("/dev/ttyS3", 9600, timeout=1)
while True:
    txt = raw_input("Type something: ")
    serport.write(txt)

No message gets to Arduino monitor....

 

Any clue?

 

Thank you,

Mapek

Edited May 17, 20197 yr by MapekCZ

Hi,

 

I solved one problem. There was just a broken wire in my circuit. 

Now... Arduino can send AT commands to SIM800l module and receives answers. 

Arduino can send messages to Orangepi and vice versa. 

 

So the module should be OK, Orangepi serial should be OK too.

But when I connect Orangepi with the module and send a message, the message returns back (as the two pins on Orangepi would have loopback wire). 

 

Mapek

Edited May 18, 20197 yr by MapekCZ