CMT2300A or inverter not connected

[deltacle]

Hardware

• [ ] ESP8266
• [X] ESP32
• [ ] Raspberry Pi

Modelname: ESP32 VROOM Retailer URL: ______

nRF24L01+ Module

• [ ] nRF24L01+ you verified this is a Plus model capable of the required 256kBit/s mode
• [ ] square dot indicates original Nordic Semicon chip
• [ ] round dot indicates copy-cat / counterfeit SI labs chip

Antenna:

• [ ] circuit board
• [ ] external antenna (SMA)

Power Stabilization:

• [ ] 100uF Electrolytic Capacitor connected between +3.3V and GND (Pin 1 & 2) of the NRF Module
• [ ] Voltage stabilizing motherboard

Version / Git SHA:

Version: 0.8.156 Github Hash: _______

Build & Flash Method:

• [X] AhoyDTU Webinstaller
• [ ] VSCode - Platform IO
• [ ] Arduino
• [ ] ESP Tools

Debugging:

• [x] USB Serial Log (attached)
• [ ] Setup settings (use our templates ... to be added)

Hello, I try to connect ahoydtu to my HMS-1600-4T (SN : 1164A00F2xxx) I have no nRF24L01, but I'm using a CMT2300A Pin connection are : SCLK : GPIO14 (HSPI SCLK) SDIO : GPIO12 (HSPI MISO) CSB : GPIO15 FCSB : GPIO26 GPIO3 : GPIO34 (in only)

I have also a display SG1106 which work very well

The first page AhoyDTU indicates the my inverter is not yet available I dont know why ? Someone can help me ?

The system display is : Radio NRF24 NRF24L01 not enabled

Radio CMT CMT2300A connected Interrupt Pin working false DTU Radio ID 89295628

Network connection WiFi (SSID: xxx_xxxx, RSSI: -53, CH: 6) Hostname AHOY-DTU IP Address 192.168.1.56 MAC Address 28:56:2F:49:xx:xx

MqTT enabled false

Memory Flash size NaNMB Config Partition (12kB of 1472kB) Firmware Partition (1269kB of 1280kB) Heap (152kB of 276kB) Heap max free block 92kB (Fragmentation: 40)

System Information Device name AHOY-DTU Uptime 0 days, 00:13:47 Reboot reason Software Environment esp32-wroom32 (build options: MDH-en) Version 0.8.156 - c4fe30f Chip CPU: 240MHz, 2 Core(s) Chip Model ESP32-D0WD-V3 Chip temp. 47.2°C

serial logs : rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT) configsip: 0, SPIWP:0xee clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00 mode:DIO, clock div:2 load:0x3fff0030,len:1184 load:0x40078000,len:13132 load:0x40080400,len:3036 entry 0x400805e4 E (538) esp_core_dump_flash: No core dum▒▒▒▒ѥѥ▒▒ found! E (538) esp_core_dump_flash: No core dump partition found! I: Initializing FS .. I: .. done I: Config Version: 11 I: Settings valid: true

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Welcome to AHOY!

point your browser to http://192.168.4.1 (Password: esp_8266) to configure your device

E: failed to set static IP! connect to network 'SFR_4FC8' I: added inverter HMS1164a00f2f32 I: Network connected E: failed to set static IP!

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Welcome to AHOY!

point your browser to http://192.168.1.56 (Station WiFi) to configure your device

I: get time from: 5.189.185.174 I: [NTP]: 2025-08-22 17:16:18 UTC

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I: com loop duration: 465ms

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I: com loop duration: 465ms

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[Gubi2023]

Interrupt Pin working false! this is the reason! Either wrong/bad connection or cold solder joint is your DTU bought ready or made by yourself?

[deltacle]

I'm using the test card module CMT2300A 868/915MHz CDEBYTE E49-900MBL-01 bought on aliexpress like this one : https://www.amazon.fr/EBYTE-module-CMT2300A-E49-900MBL-01-Distance/dp/B0BY8DL1H9

I already check the pin connection : SCLK : GPIO14 (HSPI SCLK) SDIO : GPIO12 (HSPI MISO) CSB : GPIO15 FCSB : GPIO26 GPIO3 : GPIO34 (in only)

[Gubi2023]

Where did you get this wiring from? please see this one: https://ahoydtu.de/img/fritzing/esp32-38_cmt_sch.png

[deltacle]

I don't uses exactly the same wiring, the GPIO id are not the same. I will update with you wiring.

Else which card with module CMT2300A do you suggest to use ?

[deltacle]

I update the config with the wiring Radio (CMT2300A)

CMT2300A radio enable

SCLK: GPIO12 (HSPI MISO) SDIO: GPIO14 (HSPI SCLK) CSB: GPIO27 FCSB; GPIO26 GPIO3: GPIO34 (in only)

but the "Interrupt Pin working" is always off

[Gubi2023]

does your pinmapping.json match with your wiring?

[deltacle]

Yes it seems to be right : "nrf":{"cs":5,"ce":4,"irq":16,"sclk":18,"mosi":23,"miso":19,"en":false}, "cmt":{"csb":27,"fcsb":26,"irq":34,"dio":14,"clk":12,"en":true}

[Gubi2023]

is your wiring with dupont-cables? can you test it with a measuring device? maybe there is broken cable or something else

[deltacle]

I have some news! I tested today with another ESP32 and another dupont cables, there is no change, I have the same behaviour.

But, after the power on if I disconnect the cable GPIO3, "Interrupt Pin working" switch to on. If I start with GPIO3 disconnected, "Interrupt Pin working" is also on.

So, is GPIO3 mandatory ?

Il will check tomorrow, if I can now connect to the inverter.

[deltacle]

Thanks for your help Gubi2023, the connection with the inverter works !

[siwakornp1-ship-it]

@deltacle where gpio3 on cmt2300a