What is this?

Custom Firmware for a Solax WIFI USB Stick as an esp32/8266

This works with the ESP8266 Arduino platform

https://github.com/esp8266/Arduino

This works with the ESP32 Arduino platform

https://github.com/espressif/arduino-esp32

ESP8266

Pinout of ESP

ESP	USB
GND (USB)	GND
VIN (USB)	5V
GPI01 (TX)(USB)	TX
GPI03 (RX)(USB)	RX

ESP	DEBUG USB
GPI02	RX

TODO: add image

Features

Implemented Features:

• Built-in simple Webserver
• Simple Webhook
• The data received will be transmitted by MQTT to a server of your choice.
• The data received is also provied as JSON
• Wifi manager with own access point for initial configuration of Wifi and MQTT server
• TLS support for esp32

Supported microcontrollers

• NODEMCU V1 (ESP8266) with a Solax Inverter connected via USB (USB-Serial Chip: CH340)

Supported Inverters

• X1 Mini

Structure

JSON

For ENDPOINT Data and sended post request

{
    "gridVoltage": number,
    "gridCurrent": number,
    "gridPower": number,
    "pv1Voltage": number,
    "pv1Current": number,
    "pv2Voltage": number,
    "pv2Current": number,
    "pv1Power": number,
    "pv2Power": number,
    "gridFrequency": number,
    "mode": number,
    "eTotal": number,
    "eToday": number,
    "temp": number,
    "runTime": number,
}

Code

Still missing freatures are:

• Parse Serial
• Parse Settings
• pwr limit

Notice: Only the register dongle and request data is tested

Build of request

Spezial thanks go to @tuxmike

Message structure (header, payload, checksum)

Byte offset	Datatype	Description	Value
0	uint16	Static preamble	0xAA 0x55
2	uint8	Total msg frame size (byte)	size of: header + payload + checksum
3	uint8	Cmd control code	e.g. 0x01
4	uint8	Cmd function code	e.g. 0x8C
5	...	payload	see cmd table
[Frame size-2]	uint16	Checksum	uint16 binary sum of all msg bytes

Commands

Control code	Function Code	Payload length (byte)	Checksum length (byte)	Description
01	05	0	2	Request read serial numbers
01	85	40	2	Response read serial numbers
02	01	10	2	Request register pocket dongle serial number
02	01	10	0 (!)	Response register pocket dongle serial number
01	16	0	2	Request inverter settings
01	96	400	2	Response inverter settings
01	0C	0	2	Request inverter data
01	8C	200	2	Response inverter data
01	04	0	2	Request inverter error data
01	84	44	2	Response inverter error data
05	00	2	2	Request enter pin
05	42	2	2	Request write setting pwr limit value
05	60	2	2	Request write setting pwr limit on/off
03	80	0	2	Response enter pin ok
03	81	0	2	Response setting write ok

Response serial numbers (Control code=0x01, FuncCode=0x85)

Byte offset	Datatype	Description
0	char[14]	Inverter serial number
14	char[14]	Inverter serial number padding, spaces
28	uint16	Inverter model code
30	char[8]	Pocket dongle serial number
38	uint16	Inverter model type

Request / Response register pocket dongle serial number (Control code=0x02, FuncCode=0x01)

Byte offset	Datatype	Description
0	char[10]	Pocket dongle serial number

Response inverter data (Control code=0x01, FuncCode=0x8C)

Byte offset	Datatype	Description	Unit
0	uint16	Grid voltage	0.1V
2	uint16	Grid current	0.1A
4	uint16	Grid power	1W
6	uint16	PV1 voltage	0.1V
8	uint16	PV2 voltage	0.1A
10	uint16	PV1 current	0.1V
12	uint16	PV2 current	0.1A
14	uint16	PV1 power	1W
16	uint16	PV2 power	1W
18	uint16	Grid frequency	0.01Hz
20	uint16	Mode	See Invertermodes
22	uint32	E Total	0.1kwh
26	uint16	E Today	0.1kwh
28	?	?	?
...	...	...	...
78	uint16	Inverter Temperature	°C
82	uint32	Runtime-total	1h
86	?	?	?
...	...	...	...
110	uint8	0x1B ?	?
...	...	...	...

Inverter Modes

Code	Description
0	Waiting
1	Checking
2	Normal
3	Fault
4	Permanent Fault
5	Update
6	Off-grid waiting
7	Off-grid
8	Self Testing
9	Idle
10	Standby

Response inverter error data (Control code=0x01, FuncCode=0x84)

Byte offset	Datatype	Description	Unit
0	uint16	PV1 voltage	0.1V
2	uint16	PV2 voltage	0.1V
4	uint16	?	?
6	uint16	Grid voltage	0.1V
8	uint16	Grid frequency	0.01Hz
10	?	?	?
...	...	...	...

Response inverter settings (Control code=0x01, FuncCode=0x96)

Byte offset	Datatype	Description	Unit
0	uint16	VAC low	0.1V
2	uint16	VAC high	0.1V
4	uint16	FAC low	0.01Hz
6	uint16	FAC high	0.01Hz
8	uint16	?	0.1?
12	uint16	VAC 10m avg	0.1V
14	uint16	VAC low slow	0.1V
16	uint16	VAC high slow	0.1V
18	uint16	FAC low slow	0.01Hz
20	uint16	FAC high slow	0.01Hz
...	...	...	...
208	uint16	Settings PIN A	decimal
250	uint16	Settings PIN B (?)	decimal
280	uint16	Start time	s
...	...	...	...

Request enter pin (Control code=0x05, FuncCode=0x00)

Byte offset	Datatype	Description	Unit
0	uint16	PIN	decimal

Request write setting pwr limit value (Control code=0x05, FuncCode=0x42)

Byte offset	Datatype	Description	Unit
0	uint16	power limit	W

Request write setting pwr limit on/off (Control code=0x05, FuncCode=0x60)

Byte offset	Datatype	Description	Unit
0	uint16	power limit on/off	0U=off, 1U=on

Values that are missing

• Battery If you have a battery connected to your inverter -> You can read the values out and print it in a issue.