User manual

Basys MX3™ Board Reference Manual
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Page 14 of 56
Figure 3.1. LED schematic diagram.
3.1 Connectivity
Label
Schematic
name
PIC32 pin
Description
LD0
LED0
TMS/CTED1/RA0
Led 0
LD1
LED1
TCK/CTED2/RA1
Led 1
LD2
LED2
SCL2/RA2
Led 2
LD3
LED3
SDA2/RA3
Led 3
LD4
LED4
TDI/CTED9/RA4
Led 4
LD5
LED5
TDO/RA5
Led 5
LD6
LED6
TRCLK/RA6
Led 6
LD7
LED7
TRD3/CTED8/RA7
Led 7
Table 3.1. LED connectivity.
All the pins must be defined as digital output (their corresponding TRIS bit must be set to 0):
TRISAbits.TRISA<0-7> = 0; // LED<0-7> configured as output
3.2 Functionality
To turn an LED on or off, turn the corresponding digital output pin high or low by writing 1 or 0 to the
corresponding LATA register bit.
LATAbits.LATA<0-7> = 1; // turn led on
or
LATAbits.LATA<0-7> = 0; // turn led off
Library functions for using the LEDs are contained in the Basys MX3 library pack, LED library; however, the user can
easily use the LEDs without the LED library, as presented above.
4 User Switches
Eight switches are provided, labeled SW0 – SW7 on the board and in the schematic, attached to eight digital I/O
pins of the PIC32. Reading the switches is done by basic access to an input I/O pin. Read more details in Digital
Inputs and Outputs section.
Figure 4.1 shows the way the switches are electrically connected on the Basys MX3.