isgood-scanner

ESP8266 based microcontroller code to use the MH-ET LIVE Barcode scanner module with isgood

Configuration

Configuration in this implementation is done by creating your own Settings.h in the folder include with the following content:

#include <Arduino.h>

const int8_t SCANNER_RX_PIN = D6;
const int8_t SCANNER_TX_PIN = D7;
const unsigned long SCANNER_SERIAL_BUFFER_TIMEOUT = 50;

const int8_t OLED_SCL_PIN = D1;
const int8_t OLED_SDA_PIN = D2;
const int8_t OLED_SCREEN_WIDTH = 128;
const int8_t OLED_SCREEN_HEIGHT = 32;
const int8_t OLED_RESET_PIN = -1;

const String WIFI_SSID = "wifi";
const String WIFI_PASSWORD = "password";

const String OTA_HOSTNAME = "hostname";
const String OTA_USERNAME = "username";
const String OTA_PASSWORD = "password";

uint8_t MQTT_BROKER_IP[] = {127, 0, 0, 1};
uint16_t MQTT_BROKER_PORT = 1883;
const unsigned long MQTT_DELAY = 1000;
const String MQTT_BROKER_USERNAME = "username";
const String MQTT_BROKER_PASSWORD = "password";

const char *ISGOOD_TOPIC_BARCODE = "product/barcode";
const char *ISGOOD_TOPIC_BESTBEFORE_SET = "product/best_before/set";
const char *ISGOOD_TOPIC_BARCODE_REMOVE = "product/barcode/remove";
const char *ISGOOD_TOPIC_SCANNEDAT_GET = "product/scanned_at/get";
const char *ISGOOD_TOPIC_SCANNEDAT_PUBLISH = "product/scanned_at/publish";
u_int8_t ISGOOD_CONFIG_BESTBEFORETIMEOUT = 15;

Structure

Any configuration command consists of four parts:

• command prefix (~M)
• option code
• value
• command suffix (.)

The option code and the value are hex encoded decimal values which are converted to a string and transmitted over a serial connection.

The module returns different values:

• [ACK]: Command and value were set successfully
• [NAK]: Command was valid but value was invalid
• [ENQ]: Command was invalid

Any parameter can be queried by using the command prefix ~Q instead of ~M. The response is one of

• <option code><value>[ACK]: Query was successful and option and value are returned
• [ENQ]: Command was invalid

The scanner can also be controlled in manual mode and scanning can be triggered by sending ~T. as code. The response is one of

• T[ACK]: Manual scan successful
• T[NAK]: Manual scan not successful

Option codes:

Special codes

Code	Description
A5F0	Special code to access save and restore functions, only documented with value 1B2C to fully reset device, 506A to save user settings, 8F37 to restore user defaults and D201 to delete user defaults; using this command with other values are untested and could brick the device
0091	Setup code, enters and leaves configuration mode
00F5	Sets baud rate
F672	Read module information
FA50	Read all setup codes

Operation codes

Code	Description
0001	Enable or disable all 1D codes
0002	Enable or disable all 2D codes
0021	System working mode
0022	Sleep settings for continuous mode
0023	Sensitivity of sensing in induction mode
0024	Horizontal mirroring
0025	Vertical mirroring
0026	Night vision for induction mode
0073	Trigger mode answer (1)
0086	Fill light in trigger mode
0092	Line breaks on output
0093	TAB option (1)
0094	Automatically add prefix
0095	Automatically add suffix
009B	Code ID mode (1)
009C	Convert output to uppercase or lowercase
00B0	Same code identification delay
00B1	Single reading time
00B2	Reading interval
00EA	Tone mode for bootup
00EB	Tone mode for decode
00EC	Tone mode for configure
00FA	Volume for bootup tone
00FB	Volume for decode tone
00FC	Volume for configuration tone
0103	Fill light in continuous mode
0105	Aiming light (1)
010A	Startup indicator
010B	Decoding indicator
010C	Successful configuration indicator
0126	Fill light in induction mode
0145	Enable or disable Codebar codes
0150	Enable or disable Code128 codes
0160	Enable or disable Code39 codes
0185	Enable or disable "Interleaved 2 of 5" codes
01B0	Enable or disable QR codes
01BA	Enable or disable UPC/EAN/JAN codes
01C0	Enable or disable Code93 codes
01E5	Enable or disable "Industrial 2 of 5" codes
0200	Enable or disable "Matrix 2 of 5" codes
1000	Enable or disable Code11 codes
1100	Enable or disable MSI codes
1200	Enable or disable GS1 Databar codes
1300	Enable or disable ISBN codes
1326	Enable or disable ISSN codes
1353	Enable or disable CODE32 codes

(1): I really dont know what this does and I need to test it. Please use with caution!

All option codes with specified values can be found in the file MHET_Live_Barcode_Scanner.h.

Time calculation

The official documentation has preprinted timings for several delays and interrupts. They are calculated by the basis of 100ms, converted to hex and injected to the string.

The AutomaticModeSingleReadingTimeDelay uses the option code 00B1. The timing delay for five seconds is the hex converted value of 50 (as 50 times 100ms is 5s). The complete command would be ~M00B10032..

It should be possible to inject a custom timing value with this procedure to the scanner module, but this needs testing.