70009 Parallax Inc, 70009 Datasheet - Page 101

• Manufacturer Part Number: 70009
• Description: BOOK UNDERSTANDING SIGNALS
• Manufacturer: Parallax Inc
• Type: Signal Analysisr

Specifications of 70009

• Style: Book
• Title: Understanding Signals
• Contents: Guide to Generate, View and Measure Wave Forms
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Other names: 70009PAR

IR_pulse
counter
type
IR_message
' -----[ Initialization ]--------------------------------------------------
DEBUG CLS
' -----[ Main Routine ]----------------------------------------------------
DO
LOOP
' -----[ Subroutine - Display Heading in Debug Terminal ]------------------
Display_Heading:
' -----[ Subroutine - Find and Display Start Pulse ]-----------------------
' Packets are delivered around 20 times/second while a given button on the
' remote is pressed and held.
' an earlier packet.
' of the pulse values a few packets later.
' applications, the duration of the start pulse can simply be discarded.
Find_and_Display_Start_Pulse:
DO
LOOP UNTIL IR_Detect = 0
GOSUB Display_Heading
GOSUB Find_and_Display_Start_Pulse
GOSUB Process_IR_Pulses
GOSUB Display_IR_Pulse_Values
GOSUB Convert_to_Binary_Number_Display
DEBUG HOME
DEBUG "IR Remote Messages ", CR, CR
DEBUG "Pulse Duration Value", CR
DEBUG "-------------------------------", CR
RETURN
FOR counter = 0 TO 15
PULSIN IR_detect,active_low,IR_pulse(0)
IF IR_pulse(0) > 900 THEN
DEBUG "Start"
DEBUG " = ", DEC5 IR_pulse(0) * 2, " us "
DEBUG " Start Bit", CR
EXIT
VAR
VAR
VAR
VAR
The Process IR Pulses subroutine picks up the rest
Word(12)
Nib
Nib
Byte
This program extracts a start pulse from
In remote controlled
' BOE reset clears display.
' Wait for IR detector output
' to go low.
' Exit FOR...NEXT after start