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CY3270 PSoC® FirstTouch™ Kit Guide, Document No. 001-15945 Rev. *D
Hardware
Figure 4-8. Light Sensor Schematic
Ambient light sensors consist of a filter to sample visible light, a photo diode for detection of bright-
ness, a digital filter, and a digital/analog converter. They are able to detect the intensity of surround-
ing light.
Figure 4-9. Proximity Sensor Schematic
The proximity detector requires the use of a proximity antenna and can sense an object within
approximately 2 to 3 inches of range. In the FirstTouch Kit, this sense antenna is formed by attaching
the provided wire into the pin socket labeled PRX1.
Note
Upon power-up, the FTMF establishes a baseline reading of the proximity antenna. It is, there-
fore, necessary to connect the proximity antenna prior to plugging in the FirstTouch kit.The project is
set up to recalculate this baseline approximately every 30 seconds. Note how the shape and position
of the wire affects the demonstration operation and the proximity sensing distance.
4.4.1.1
CY8C21434 Chip
The FTMF expansion card connects the various sensors and output devices to a predefined I/O of
the host CY8C21434. It is important that you follow the pin assignment shown in
and
. Port P0[6] “LSENSE” is connected to the light sensor to receive signals for light sensitivity,
P0[0] to sense temperature incident on the MF card. P1[6] drives a buzzer. P1[2], P1[3], and P1[4]
are driving LED blue, red, and green respectively. P2[1] to P2[7] sense the touch on the 7-element
CapSense region of the card.
Ambient Light
Detector
LSENSE
VEXP
+
PR1
LX1972A
1
2
0
6
03
R19
4.99K 1%
Ambient Light
Detector
LSENSE
VEXP
+
PR1
LX1972A
1
2
0
6
03
R19
4.99K 1%
