Pocket Nurse

All the materials needed have come! This is the final arrival.

In this picture we could see (listed form above to below):

• LCD 16x2
• Rechargeable battery
• Micro SD card Shiel for Arduino
• LDR
• Green high bright LED
• Solar module 3,3 V
• Arduino Nano ATmega 328 customed from China

Well after waiting for weeks, I've received my displays.

I must calibrate the contrast, but with a 4.7 kOhms resistor connected to ground it works great.

There is a lot of cables around but they are connected in the right place.

I will be waiting for the arrival of the ATmega328... I'm using a Arduino UNO meanwhile.

According to the rules of the Trinket Everyday Carry Contest I must use a Pro Trinket. So while I'm waiting for the Pro Trinket I will be using my Nano Arduino. But it's temporary until I receive Pro Trinket.

Also I'm still waiting for the main components...

IMPORTANT!!

I am waiting for the materials. I will be waiting till christmas I hope so, shipping to Uruguay could be cruel.

Heart Beat Detector

I found this image on the internet, and it describes how to build a heart beat detector. It uses an infrarred receiver (infrarred sensitive photoresistor as it´s shown in the picture), and a infrarred transmitter.

The infrarred emitter sends a infrarred light through the finger (or some translucent part of the body), and with each pulsation of the hearth it reduces the intensity of the light that could pass. So the infrarred sensitive photoresistor receives a variable light on the other side of the finger, and when the intensity decreases there is a pulse.

The nano arduino will count how many of these interruptions could be in a minute.