User manual

Chapter 6. User Circuitry

6.1. Switches

There are four switches located on the RSK board. The function of each switch and its connection are shown in Table 6-1

Switch Function Microcontroller

RES When pressed, the microcontroller is reset. RESETn, Pin 9

SW1 / BOOT* Connects to an INT input for user controls.

The switch is also used in conjunction with the RES switch to place the

device in BOOT mode when not using the E8a debugger.

INT1n, Pin 35 (Port 3, bit 6)

SW2* Connects to an INT line for user controls. INT2n, Pin 46 (Port 6, bit 6)

SW3 / ADTRG* Connects to an INT line for user controls. The same MCU pin also

functions as ADC trigger input.

INT0n, Pin 48 (Port 4, bit 5)

Table 6-1: Switch Functions

*Refer to the schematic for detailed connectivity information.

6.2. LEDs

There are six LEDs on the RSK board. The green ‘POWER’ LED lights when the board is powered. The orange ‘BOOT’ LED indicates the

device is in BOOT mode when lit. The four user LEDs are connected to an I/O port and will light when their corresponding port pin is set

low.

Table 6-2 below shows the LED pin references and their corresponding microcontroller port pin connections.

LED Reference (As

shown on silkscreen)

Colour Microcontroller Port

Pin function

Microcontroller

Pin Number

LED0 Green Port 0, bit 0 72

LED1 Orange Port 0, bit 1 71

LED2 Red Port 0, bit 2 70

LED3 Red Port 0, bit 3 69

Table 6-2: LED Port

6.3. Potentiometer

A single-turn potentiometer is connected to pin AN8 (Port 1 bit 0, pin 56) of the microcontroller. This may be used to vary the input analog

voltage value to this pin between AVCC and Ground.

Note: The potentiometer is fitted to offer an easy way of supplying a variable analog input to the controller. It does not necessarily reflect

the accuracy of the controller’s ADC. Please see the device manual for details.