Freescale Semiconductor MPC5748G EVB, Руководство пользователя

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User Interface (I/O)
MPC5748G EVB User Guide, User Guide, Rev. 0, 08/2015
Freescale Semiconductor, Inc. 29
8.4. User LED’s (DS2, DS3, DS7, DS8, P19)
There are four active low user LED’s connected directly to 4 MCU ports (PG[2..5]) as well as to a 4 pin
header.
Table 23. User LEDs (DS2, DS3, DS7, DS8, P19)
Switch Number MCU Pin P19 Connection Pin
DS2
1 PG2 Pin1 (Upper Pin)
DS3 2 PG3 Pin2
DS7 3 PG4 Pin3
DS8 4 PG5 Pin4
NOTE
The MCU ports used on the LEDs are also routed to the GPIO matrix.
There are zero ohm resistors on the direct connections between each LED
and the MCU pins. These can be removed if required to isolate the LED
from the respective MCU pin (useful if the LED is being manually routed
to another pin on the GPIO matrix).
8.5. ADC Input Potentiometer (J17, RV1)
There is a small variable resistor RV1 on the EVB which routes a voltage between 0v and 3.3V to MCU
pin PB4. This is useful for quick ADC testing. Jumper J17 which is fitted by default can be removed to
disconnect MCU PB4 from RV1 if desired.
Table 24. ADC Input Potentiometer Enable (J19)
Jumper Position PCB Legend Description
J17
FITTED (D)
Output from RV1 is routed to MCU PB4 pin
Removed
MCU PB4 is not connected to RV1
There is also a test point TP18 connected to the variable resistor output for monitoring purposes.
The
user LED’s are
above the user
switches in the lower
right quarter
The ADC Pot is to
the right of the user
LED’s in the lower
right corner