ESP8266 mDash

Questions & Answers
1

The ESP8266 crashes when using the library “api_aws.js” or “api_mqtt.js” after successfully connecting to the AWS IoT server and receiving a “curve 3” response. This only happens when you register the device with mDash using “api_dash.js”

NB The are no such problems with any combination of these libraries using the ESP32.

[May 17 11:21:07.313] SW ECDH curve 3
[May 17 11:21:14.014] E:M 32 (5 blocks)
[May 17 11:21:14.016]
[May 17 11:21:14.016] Exception 29 @ 0x4000e1b2, vaddr 0x00000000
[May 17 11:21:14.020] A0: 0x402919ab A1: 0x3ffff7a0 A2: 0x00000000 A3: 0x00000000
[May 17 11:21:14.026] A4: 0x00000020 A5: 0x00000000 A6: 0x00000020 A7: 0x00000002
[May 17 11:21:14.031] A8: 0x3ffe83cc A9: 0x00000190 A10: 0x00000000 A11: 0x0000007c
[May 17 11:21:14.037] A12: 0x00000000 A13: 0x00000020 A14: 0x00000001 A15: 0x3ffff830
[May 17 11:21:14.047]
[May 17 11:21:14.047] (exc SP: 0x3ffff600)
[May 17 11:21:14.047]
[May 17 11:21:14.047] — BEGIN CORE DUMP —
[May 17 11:21:14.047] mos: catching core dump

This also happens when you use the demo code (https://github.com/mongoose-os-apps/demo-js) and compile with Mongoose OS command line tool Version: 2.13.1

Does anyone have any solutions for this situation?

2

[May 17 11:21:14.014] E:M 32 (5 blocks)

You are out of RAM.
Before connecting to AWS, make sure you have at minimum ~30k free RAM.

3

Thanks, we will free up some ram and test.

4

Hi, SO we have installed the Mongoose demo code on the ESP8266 and we are still getting issues with the core dump.

[May 19 21:58:13.583] mgos_net.c:101 WiFi STA: ready, IP 192.168.254.174, GW 192.168.254.254, DNS 192.168.254.254
[May 19 21:58:13.592] mgos_provision_state:43 Current state: 1 -> 2
[May 19 21:58:13.599] mgos_rpc_channel_ws:260 0x3fff0e14 Connecting to wss://dash.mongoose-os.com/api/v2/rpc, SSL? 1
[May 19 21:58:13.618] mgos_mqtt.c:427 MQTT connecting to a1k3q7ebae2sxe-ats.iot.us-east-1.amazonaws.com:8883
[May 19 21:58:13.660] mgos_mongoose.c:66 New heap free LWM: 19800
[May 19 21:58:13.886] mgos_mongoose.c:66 New heap free LWM: 17432
[May 19 21:58:13.894] mg_ssl_if_mbedtls.c:35 0x3fff3184 ciphersuite: TLS-ECDHE-RSA-WITH-AES-128-GCM-SHA256
[May 19 21:58:14.376] E:M 264 (34 blocks)
[May 19 21:58:14.376]
[May 19 21:58:14.376] Exception 29 @ 0x4000e1b2, vaddr 0x00000000
[May 19 21:58:14.383] A0: 0x402972b3 A1: 0x3ffff1b0 A2: 0x00000000 A3: 0x00000000
[May 19 21:58:14.389] A4: 0x00000108 A5: 0x00000000 A6: 0x00000100 A7: 0x00000010
[May 19 21:58:14.393] A8: 0x3ffe83cc A9: 0x00000190 A10: 0x00000000 A11: 0x0000007c
[May 19 21:58:14.398] A12: 0x00000000 A13: 0x00000108 A14: 0x00000003 A15: 0x3ffff240
[May 19 21:58:14.410]
[May 19 21:58:14.410] (exc SP: 0x3ffff010)
[May 19 21:58:14.410]
[May 19 21:58:14.410] — BEGIN CORE DUMP —
[May 19 21:58:14.410] mos: catching core dump
[May 19 21:58:17.249] …read err EOF

5

Confirmed, the pre-built demo-js firmware crashes with out-of-memory when connecting to AWS IoT.
Apparently, some latest changes in Mongoose OS libraries increased RAM consumption. Could you dump a list of libraries you’re using in your firmware please?

6

Hi,
I am getting the memory error on the unmodified demo.js example found here:

Here are the unaltered libraries that the demo mos.yml
libs:

Here are the unaltered APIs that are loaded in the demos init.js

load(‘api_aws.js’);
load(‘api_azure.js’);
load(‘api_config.js’);
load(‘api_dash.js’);
load(‘api_events.js’);
load(‘api_gcp.js’);
load(‘api_gpio.js’);
load(‘api_mqtt.js’);
load(‘api_shadow.js’);
load(‘api_timer.js’);
load(‘api_sys.js’);
load('api_watson.js’);

Here us a dump of the file system:
$ mos ls
api_adc.js
api_arch_uart.js
api_aws.js
api_aws.jsc
api_azure.js
api_azure.jsc
api_bitbang.js
api_config.js
api_config.jsc
api_dash.js
api_dash.jsc
api_dataview.js
api_dht.js
api_esp8266.js
api_events.js
api_events.jsc
api_file.js
api_gcp.js
api_gcp.jsc
api_gpio.js
api_gpio.jsc
api_http.js
api_i2c.js
api_log.js
api_math.js
api_math.jsc
api_mqtt.js
api_mqtt.jsc
api_neopixel.js
api_net.js
api_ota.js
api_pwm.js
api_rpc.js
api_shadow.js
api_shadow.jsc
api_spi.js
api_sys.js
api_sys.jsc
api_timer.js
api_timer.jsc
api_uart.js
api_watson.js
api_watson.jsc
api_wifi.js
ca.pem
conf0.json
init.js
init.jsc

7

Yeah, that’s clear, thank you! We’re looking at the issue.

8

The problem was tracked down to the AWS IoT cloud being changed on-site certificates, which increased the RAM consumption on a device during TLS handshake.
So that was unrelated to any device-side changes.
However, optimised RAM usage during handshake, and that fixed an issue.