FYP S2 WEEK 3

Tittle of activity :

• Search and construct ultrasonic sensor max sonar-EZ1 circuit.

Objective :

• Use suitable sensor that can relate or function with PIC16F877A

Content/procedure :

Component needed

• LCD
• Maxsonar EZ1
• NPN transistor 2N2222
• Breadboard
• Jumper Wire
• Resistor (1k & 4.7k)

Circuit Connection

Simulation Connection

Result and analysis :

Maxsonar-EZ1

The Maxsonar-EZ1 sensor offer a very short to long range detection which is from 0-inches to 254-inches plus with a very low power consumption. It has provided sonar range information from 6-inches out to 254-inches with 1-inches resolution. Object from 0-inches to 6-inches are range as 6-inches. It has 3 modes selection for the output range which is:

~ Serial, 0V – 5V, 9600 Baud
~ Analog, 10mV/inch
~ Pulse Width, 147us/inch

EUART of PIC16F887

The Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) module is a serial I/O communication peripheral. It is also known as Serial Communications Interface (SCI). It contains all clock generators, shift registers and data buffers necessary to perform an input or output serial data transfer independently of the device program execution. As its name states, apart from the usage of clock for synchronization, this module can also establish asynchronous connection, which makes it irreplaceable in some applications.

Conclusion :

• Maxsonar-EZ1 will send the output if in ASCII format. For maxsonar-EZ1 sensor, the output are in RS232 format which mean that the HIGH(1) bit are at 0V while the LOW(0) bit are 5V, so need to connect the TX of sensor connect to NPN while RX of sensor to TX of microcontroller as shown in figure above.