Leo at 05:28, 2 August 2025

2025-08-02T05:28:21Z

← Older revision		Revision as of 05:28, 2 August 2025
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	=== Wireless support? ===		=== Wireless support? ===
			[[File:PTH-9C Board.jpg\|alt=PTH-9C Board\|thumb\|PTH-9C Board]]
	The PTH-9C does not come with any wireless capabilities, unlike the PTH-9CW model. However, it appears that the main board is identical to the PTH-9CW with some components, including the crucial tuya chip missing.		The PTH-9C does not come with any wireless capabilities, unlike the PTH-9CW model. However, it appears that the main board is identical to the PTH-9CW with some components, including the crucial tuya chip missing.

Leo: Created page with "The Inkbird PTH-9C is a 3-in-1 CO2/temperature/humidity detector with a LCD display. It has a Winsen MH-Z19E sensor which is capable of detecting CO2 between 400 and 10,000 ppm, although the firmware in this device only reports up to 5,000 ppm. === Wireless support? === The PTH-9C does not come with any wireless capabilities, unlike the PTH-9CW model. However, it appears that the main board is identical to the PTH-9CW with some component..."

2025-08-02T05:11:28Z

Created page with "The Inkbird PTH-9C is a 3-in-1 CO2/temperature/humidity detector with a LCD display. It has a Winsen MH-Z19E sensor which is capable of detecting CO2 between 400 and 10,000 ppm, although the firmware in this device only reports up to 5,000 ppm. === Wireless support? === The PTH-9C does not come with any wireless capabilities, unlike the PTH-9CW model. However, it appears that the main board is identical to the PTH-9CW with some component..."

New page

The Inkbird PTH-9C is a 3-in-1 CO2/temperature/humidity detector with a LCD display. It has a [[MH-Z19 Carbon Dioxide Sensor|Winsen MH-Z19E]] sensor which is capable of detecting CO2 between 400 and 10,000 ppm, although the firmware in this device only reports up to 5,000 ppm.

=== Wireless support? ===
The PTH-9C does not come with any wireless capabilities, unlike the PTH-9CW model. However, it appears that the main board is identical to the PTH-9CW with some components, including the crucial tuya chip missing.

Is it possible to solder a ESP8266 chip on the existing pads and take readings? Likely not. I don't see any serial traffic on the TX/RX pads, so the firmware that's on the unmarked IC is likely not configured to send traffic out.

If you really do want to get the CO2 sensor data, read it from the MH-Z19E directly from pin 3 (center pin on the 5 pin header) at 9600 baud 8N1. The IC on this unit polls sensor data about every 1 second with the sensor reporting measurements in this format:
{{Highlight
| code = start, command = 86, high + low, 42, 3 bytes of 0's, checksum
ff 86 01 f5 42 000000 42
ff 86 01 f5 42 000000 42
ff 86 01 f5 42 000000 42
| lang = terminal
}}
The important bits are the high+low values, which when read as <code>0x01F5</code> gives you 501 (ppm).

== See also ==

* [[MH-Z19 Carbon Dioxide Sensor|The MH-Z19 CO2 sensor]]

Inkbird PTH-9C - Revision history

Leo at 05:28, 2 August 2025