Configuration
—Motherboard
MPC5777C EVB User Guide, Rev. 1
11
NXP Semiconductors
There are four active low user LEDs D2, D3, D4 and D5, these are driven by connecting a logic 0
signal to the corresponding pin on 0.1in. header P7 (USER LEDS). The LED inputs are pulled to
VDD_HV_IO_MAIN through 10 k
resistors.
There are 4 active high pushbutton switches SW1, SW2, SW3 and SW4 which will drive 5V onto the
respective pins on 0.1in. Connector P6 when pressed. The switch outputs are pulled to GND via 10
k
.
Potentiometer RV1 can be connected to port pin PB[0] via J53 and is adjustable between GND and 5 V
from the linear regulator. Power from all regulators can be connected to port pins as through J54:
• 1-2: 1.25V_SR to PB[1]
• 3-4: 3.3V_SR to PB[2]
• 5-6: 5.0V_SR_SR to PB[3]
• 7-8: 5V_LR to PB[4]
The P12V rail from the 12 V input is scaled to 4.3V through the voltage divider of R81 and R82 and
the scaled voltage can be connected to PB[5] via J55.
3.7
Test points
—
Motherboard
A number of test points of different shape and functionality is scattered around the EVB to allow
easy access to MCU and reference signals. This chapter summarizes and describes the available test
points. Motherboard test points are listed and detailed in
Table 6: Test Points- Mother Board
Signal
TP name
Shape
Description
GND
GT1
Hook
Ground reference
GND
GT2
Hook
Ground reference
GND
GT3
Hook
Ground reference
GND
GT4
Hook
Ground reference
GND
GT5
Hook
Ground reference
GND
GT6
Hook
Ground reference
GND
GT7
Hook
Ground reference
GND
GT8
Hook
Ground reference
GND
GT9
Hook
Ground reference
GND
GT10
Hook
Ground reference
GND
GT11
Hook
Ground reference
1.25V_SR
JP1
Pin
1.25V_SR reference
