Weather measurements with Sure Modules

Having got exceedingly frustrated at not being able to interface the MPL 115A pressure sensor, I had a look at the Sure MB-SM 11111 module for measuring temperature and humidity, and the Sure DC-SS 500 for measuring temperature and air pressure.

I was drawn to these as they could be interrogated an ascii and sent back results in ascii. There didn’t seem much of a problem in interfacing.

Both the units also have SPI capabilities, but I fought shy of this.

Initial attempts were disappointing. Two Picaxe chips were needed for each module, one to send a demand and one to receive the response. The Picaxe 18x was not fast enough to do both.

Then the 18m2 arrived and everything changed. A single 18m2 was fast enough to both send the ascii string to the Sure module, and then sit and wait for the Sure data to be returned, also in ascii.

I made two units, the mast unit measuring air temperature and humidity, and the base unit measuring room temperature and air pressure. The base also receives the mast data via a 433 Mhz radio link.

As the RX / TX pair are relevant to both units, I have appended the
RF Solutions data sheet along with a picture of the display.

Details

Here are two PDFs showing the base and mast units in detail, along with relevant codes.

As usual E&OE

.......... and the Sure module data sheets.

Hi Russbow,

What an excellent project example.
Those Sure modules lok great, and they have standardised the pinouts, even better. Good find.

MPep.