Hi i was wondering how could i send, with a coap response, one's device network name and a, for exaple a temperature value, like this:
<device's network name>: <temperature value>
I tried this, but failed:
Oh, ok. So this has nothing to do with OpenThread. It has to do with the way you are trying to create a character string.
First of all, you need to change the
' '
with
" "
and lastly, I don't think the line
const char *buf[] = {CONFIG_BOARD, " ", myTemperature};
works as you intend it to.
Please have a look at what was printed from this snippet:
const char *myTemperature = "23.32";
const char *buf[] = {CONFIG_BOARD, " ", myTemperature};
LOG_INF("buf[1]: %s", buf[0]);
LOG_INF("buf[2]: %s", buf[1]);
LOG_INF("buf[3]: %s", buf[2]);
LOG_INF("location buf[0]: %p", buf[0]);
LOG_INF("location buf[1]: %p", buf[1]);
LOG_INF("location buf[2]: %p", buf[2]);
I got the log:
00> [00:00:00.004,608] <inf> peripheral_uart: buf[1]: nrf52840dk_nrf52840 00> [00:00:00.004,608] <inf> peripheral_uart: buf[2]: 00> [00:00:00.004,638] <inf> peripheral_uart: buf[3]: 23.32 00> [00:00:00.004,669] <inf> peripheral_uart: location buf[0]: 0x31414 00> [00:00:00.004,669] <inf> peripheral_uart: location buf[1]: 0x31d11 00> [00:00:00.004,699] <inf> peripheral_uart: location buf[2]: 0x3143e
Note the location of the different buffers, which are also visible during a debug session:
And if I read out the data in these locations, you can see that they are indeed not in the same place in flash:
C:\Nordic_Semiconductor\SDKs\ncs\v2.1.2\zephyr\samples\hello_world\src>nrfjprog --memrd 0x31414 --n 32 0x00031414: 3566726E 30343832 6E5F6B64 32356672 |nrf52840dk_nrf52| 0x00031424: 00303438 5B667562 203A5D32 62007325 |840.buf[2]: %s.b| C:\Nordic_Semiconductor\SDKs\ncs\v2.1.2\zephyr\samples\hello_world\src>nrfjprog --memrd 0x31d11 --n 32 0x00031D11: 20007C00 2563001B 5B313B33 316D001B | .|.%c..[1;31m..| 0x00031D21: 5B313B33 336D0065 72720077 726E0069 |[1;33m.err.wrn.i| C:\Nordic_Semiconductor\SDKs\ncs\v2.1.2\zephyr\samples\hello_world\src>nrfjprog --memrd 0x3143e --n 32 0x0003143E: 3332332E 00326F6C 61636974 6E6F6220 |23.32.location b| 0x0003144E: 6675305B 3A5D2520 00706F6C 61636974 |uf[0]: %p.locati|
And please note that all of these strings are null terminated.
So as long as you are aware that these strings are not adjacent in flash, then you can use it like this. If not, you need to set up your buffer in another way.
BR,
Edvin
