[PIC] programming in pic19f2431 using ADC giving problems in defining ports

[aishwarya_gaur]

In this pic18f2431 microcontroller i am not able to operate two LDR together. both the readings of LDR are shown by tha AN0 pin of the microcontroller ! how to get these two diffrent values on different ports? Help asap!

 

[betwixt]

Connect the LDRs to different pins, for example AN0 and AN1 then decide which is to be measured by the ADC by programming the appropriate registers.

That particular PIC has quite a complicated ADC signal routing method because it can automatically sequence through analog input pins. You will have to work out the values to be sent to the registers using the data sheet.

Brian.

 

[Okada]

If you want to display LDR1 data on PORTB and LDR2 data on PORTC then you have to configure the ADC Registers and then read the adc value and right shift the adc values 2 times and assign them to LATB and LATC.

Here is the project I made using mikrC PRO PIC Compiler.

Mention your Compiler and Crystal frequency and I will write a code for you.

See attached image. It shows the simulation result.

Voltage at adc inputs are 4.81V.

5V = 1023 raw adc value
4.81V = 984 (integer value)

984 right shifted 2 times = 246

246 = 1111 0110

The LEDs are showing the right values.