28119 Parallax Inc, 28119 Datasheet - Page 68

• Manufacturer Part Number: 28119
• Description: KIT UNDERSTANDING SIGNALS
• Manufacturer: Parallax Inc

Specifications of 28119

• Lead Free Status: Contains lead
• Accessory Type: Oscilloscope
• Interface Type: USB
• For Use With/related Products: BASIC Stamp® 2 and Board of Education
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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Configure, resize, and reposition your PC display so the OPTAscope software is
running side-by-side with the BASIC Stamp Debug display (Figure 4-12).
Set the Cursor Settings switch to Paired Bars and place the red cursor at the top of
the curve.
Place the blue cursor at about 1.4 V.
Compare your delta value measured with the OPTAscope to the data in the
BASIC Stamp Debug Terminal. The values should be very close.
Converting RCTime units to milliseconds is done in the following PBASIC line of code:
DEBUG HOME, "(time/1000)*2 = ", DEC3 (time/1000)*2
The
units of milliseconds. The (time/1000)*2 instruction manages this conversion.
Why does my Debug Terminal display 000?
If you expose your photoresistor to very low light levels, the discharge time in this circuit may
exceed 65535. This is the largest value that
Instead of allowing an overflow to occur, which would place a truncated and incorrect value
in the time variable, the
that a “timeout” occurred. This causes the Debug Terminal to display a 0, since (0/1000)*2
=0. Simply re-run your program to clear the time variable, and keep the light level on your
photoresistor a little brighter.
RCTIME
command measures in units of 2 microseconds, but OPTAscope displays in
RCTIME
command places a 0 in the time variable to let you know
RCTIME
can store in a word-size variable.