ESP8266 Community Forum

- Wed Apr 01, 2015 7:26 am #13181 The DHT22 is similar to the DHT11 but has much better accuracy. There may be some software differences, though.

The standard DHT11-schema contains a pull-up resistor but I'm not sure whether this is needed at all. (The ESP8266 will do the pull-up internally)

This board contains:
- 3x DS18(b)20 connectors. (Or any other 1-wire sensors) Using GPIO0 + pull-up resistor
- 1x HDT11 connector (Using GPIO2) + pull-up resistor
- Raspberry PI B+ interface for programming (No other hardware needed)
- ESP-01 interface for soldering or header/connector.
- Prog jumper (connecting GPIO0 to GND)
- PCD8544 interface connecting RST to ESP-01-RST via resistor and CE to GND via resistor.
- Backlight jumper/switch for PCD8544

I bought 10 of these boards and use them for everything. One for a programmer, 2 for temperature sensors, 1 as a DHT11-sensor, 1 to try to get the PCD8544 working.

What I miss, though, is a reset jumper, so I soldered a 4.7kOhm resistor between the backlight hole on the PCD8544-connector and one of the resistor-holes, which made the backlight-jumper a reset-jumper (for my programmer board).

There are no surface-mount parts, for easy DIY soldering.

Marius

- Tue Apr 14, 2015 2:53 pm #14505 I made a logger with a SHT15 I had laying around and a ESP-1. The problem I have is when booting up the module, I can't have the SHT15 connected to the IO-0 or IO-2 pins or it goes crazy since the pins are getting signal from chip or are floating. How did you handle this, or is the DHT11 different?

- Thu Apr 16, 2015 6:51 am #14696 I never had this issue

Marius

- Mon Apr 20, 2015 12:24 am #15088 I'v been using si7021 (TEMPERATURE AND HUMIDITY SENSOR) for a few months now.

SI7021 works much better than DHT11/DHT22.
power consumption is very low, and much more accurate.

Make something useful. 'Eat your own dog food' DevKit for IoT.
http://www.nodeusb.com