Power issue on ESP double deck module

On this  module power it for development/debugging from your computer USB on the lower board can lead to an very dimmed red LED.

To avoid this issue add power on the upper board also. Looks like RED led consume some power and if you have an low current USB like I have, you will not see the RED led.

Indeed red part of LED is consuming more power and is not as bright as BLUE or GREEN but is fine for development purpose.

E-ink display Part II

Now you can see the E-ink display in action.

It is connected to the ESP201 development board which also have an DS18B20 temperature sensor attached.

I've managed to reduce the pin numbers so now I can have extra pins to connect more sensors and show their values on this tiny e-ink display.

E-ink display Part I

Finally my e-ink display arrived and I had some time to test it.

At the first look it redraw the screen in about 1 second, consume very little when changing the display and nothing between the changes.

I will connect it to my battery operated Temperature and humidity sender so I can see the values during the sleep time.

E-ink aka E-paper display

 Features:

• Ultra low power consumption
• Super wide viewing angle - near 180°
• Extra thin & light
• High Resolution
• SPI interface
• Four gray shade colors
• All necessary component included
• Integrating boosted circuit

Specifications:

• Resolution: 172x72
• Display thickness: 1.18mm
• Display Dimension: 2.04inch,
• Module dimension: 30.13x60.26mm
• Pixel Pitch (mm): 0.28(H) X 0.28(V) / 95dpi
• Contrast Ratio: 10:1
• Display Color: 4 gray shade colors, White, Gray, Deep gray, Black
• Refresh Time (room temp.): 1 sec
• Interface: SPI
• Operation Temperature: 0~50°C
• Storage Temperature: -20~60°C
• Module Weight: 15g
• VCC 3.3V

New ESP8266 board

I've received a new type of module and what I can tell you that it is amazing.

It is a sandwich module, upper board is having the ESP-12F,  RGB LED, photo resistor connected to ADC pin and a button.

The lower board is having the CH341 USB to serial chip which was recognized well by Windows or Linux ( native or in Virtual Box).

Other two buttons RST (reset) and FLASH are on the lower part.

Interesting is that I don't need to put the GPIO0 to GND for flashing the board, this is done automatically, so just compile and flash with one command line.

Both boards are having micro usb connectors so you can use the one from the lower board for programming and later in production you can power the board using the connector from the ESP board.

Flashing can be done at 230400 so the time is reduced to half which is great.

Board was originally for Witty cloud, a cloud service launched in China but my board is running now a porting of mosquitto broker for ESP8266 ( I also ported it for ESP31B) and I can tell you that is more stable and more responsive then ESP31B which is in an early development stage at this time. 

You can buy the module from here for 4.23USD ( at this time). You will receive the entire module, can use the ESP board and have for "free" an extra USB to serial for other projects.

MQTT Broker on ESP32

I've managed to put an MQTT broker on ESP32 (aka ESP31B).

The code is under development and ESP32 at this time is not yet released, but when it will be I'll also have the code complete. There are some problems but let's hope they will be resolved by the Espressif System. 

I will try to see if I can do the same with ESP8266 which is already on the market.