27904 Parallax Inc, 27904 Datasheet - Page 6

• Manufacturer Part Number: 27904
• Description: ALCOHOL BENZINE GAS SENSOR
• Manufacturer: Parallax Inc

Specifications of 27904

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

BASIC Stamp
This program is designed for the BASIC Stamp 2 and a CO Gas Sensor (#27931).
' =========================================================================
'
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' -----[ Program Description ]---------------------------------------------
' This program runs the Gas Sensor Heater through two phases (voltages) as
' recommended by the manufacturer datasheet.
' least 10 minutes in clean air before any calibration is done.
' The first phase is the PURGE phase where the heater element is turned on
' at a full 5V.
' condition is done here.
' of this phase.
' The second phase is the SENSE phase where the heater element is run at
' ~1.4V for 90 seconds.
' calibrated or that the sensor is checked for alarm conditions.
' -----[ I/O Definitions ]-------------------------------------------------
HSW
ALR
' -----[ Variables ]-------------------------------------------------------
index
' -----[ Program Code ]----------------------------------------------------
Main:
Copyright © Parallax Inc.
DO
LOOP
File...... CO Gas Sensor.bs2
Purpose... Runs the CO Gas Sensor Module Heater
Author.... Parallax, Inc.
E-mail.... [e-mail]
Started... 02-09-2009
Updated...
{$STAMP BS2}
{$PBASIC 2.5}
LOW HSW
FOR index = 59 TO 0
NEXT
index = 1710
DO
LOOP UNTIL index = 0
DEBUG HOME, "PURGE MODE...", DEC2 index, "
PAUSE 1000
DEBUG HOME, "SENSE MODE...", DEC2 index / 19
LOW HSW
PAUSE 15
INPUT HSW
PAUSE 3
index = index - 1
IF ALR = 1 THEN
ELSE
ENDIF
DEBUG " ***ALARM***"
DEBUG "
PIN
PIN
VAR
®
This clears the sensor and no checking for an alarm
2 Program
Gas Sensor Modules (#27930, #27931, #27932, #27904) v2.2 8/2/2010 Page 6 of 6
0
1
Word
It is during this phase that the sensor can be
The DEBUG screen will count down the 60 seconds
"
' Heater Switch Control
' Alarm Input Sense
' Counter Variable
' Turn Heater ON
' Count Down 60 Seconds
' 1 Second Pause
' Approximately 90 Seconds
' Of Iterations On BS2
' Turn Heater ON
' For 15 ms
' Turn Heater OFF
' For 3 ms
' Decrement Counter
' Check For Alarm Condition
' Display Alarm Condition
' Clear Alarm Condition
' End Of Sense Mode Loop
The sensor should run for at
"