EVB-VF522R3 Platform User’s Guide, Rev. 0, 11/2014
Freescale Semiconductor, Inc.
25
User I/O and control
NOTE
Some of the digital I/O signals are still used elsewhere on the EVB, so you
must check availability prior to use. The signal cross-reference
should help with that.
14.2
ADC input potentiometer (RV1, TP8)
Useful for quick ADC testing, there is a small potentiometer (variable resistor) RV1 on the EVB, which
routes a voltage between 0V and 3.3V into the MCU ADC input (pin ADC0SE8). An optional test point
TP8 on this line can be used for voltage-monitoring purposes.
14.3
Radio control buttons
14.3.1
Incremental encoders (SW1, SW2)
There are two incremental rotary encoders on the EVB (24 clicks/12 pulses per rotation) with center push
switch. These are intended to be used for radio development allowing volume/mode control.
The encoders are connected to the Vybrid FlexTimer Quad Decode channels for the rotation detection and
to a GPIO for the center button push (see
).
Table 7. Connector P14 (digital)
Signal
Pin No
Pin No
Signal
FB_AD16
1
2
FB_AD17
FB_AD24
3
4
FB_AD25
FB_AD26
5
6
FB_AD29
FB_AD30
7
8
FB_AD31
SAI0_RX_BCLK
9
10
LVDSON
QSPI0_A_DQS
11
12
LVDSOP
QSPI0_B_DQS
13
14
FTM0CH5
GND (Digital)
15
16
GND (Digital)
Table 8. Incremental encoders
Encoder
GPIO
FTM Channels
SW1
FB_AD24
CHA – FB_AD19 (QD_PHA)
CHB – FB_AD18 (QD_PHB)
SW2
FB_AD25
CHA - FTM1CH0 (QD_PHA)
CHB - FTM1CH1 (QD_PHB)
