1818281+1818282 Microchip Technology, 1818281+1818282 Datasheet - Page 36

• Manufacturer Part Number: 1818281+1818282
• Description: EDF / AMICUS18 + SHIELD, BUNDLE
• Manufacturer: Microchip Technology
• Type: Development Boardr

Specifications of 1818281+1818282

• Kit Contents: Board
• Svhc: No SVHC (15-Dec-2010)
• Kit Features: Nine 10-bit ADC Inputs, Two 10-bit PWM Outputs, Two Comparators
• Mcu Supported Families: PIC18F25K20
• Silicon Manufacturer: Microchip
• Core Architecture: PIC
• Core Sub-architecture: PIC18
• Silicon Core Number: PIC18F
• Silicon Family Name: PIC18FxxKxx

Light Level Switch (Moth Mode)
The same circuit and layout is used for the opposite reaction to light levels. The code below will illumi-
nate the LED when light levels increase, just like a moth to a flame.
' Illuminate an LED when an LDR connected to AN0 sees light
' Altering the value within the If-Then condition will set the dark level threshold
' Any value from 0 to 1023 is valid, however, smaller values indicate lightness
'
' Open the ADC:
'
'
'
'
'
The code is essentially the same as cockroach mode, except the LED illuminates when the ADC value is
less that 400, instead of greater than 400.
Crownhill AssociatesLimited 2009 - All Rights Reserved
Dim LDR_Value As Word
Symbol LED = RB0
Include
OpenADC(ADC_FOSC_32 & ADC_RIGHT_JUST & ADC_2_TAD, ADC_REF_VDD_VSS, ADC_1ANA)
While 1 = 1
Wend
LDR_Value = ReadADC(0)
If LDR_Value <= 400 Then
Else
EndIf
DelayUS 30
High LED
Low LED
"ADC.inc"
Fosc set for Fosc / 32
Right justified for 10-bit operation
Tad value of 2
Vref+ at Vcc : Vref- at Gnd
Make AN0 an analogue input
Amicus18 Companion Shield
Version 1.0
' Holds the 10-bit ADC value from the LDR
' Pin where the LED is connected. i.e. bit-0 of PortB
' Load the ADC macros into the program
' Create an infinite loop
' Read the ADC value from AN0
' Is the ADC value less than 400. i.e. getting lighter
' Yes. So illuminate the LED
' Otherwise...
' Extinguish the LED
' Allow the ADC to recover
' Do it forever
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06-10-2009