User manual

Chapter 6. User Circuitry
6.1. Switches
There are four switches located on the board. The function of each switch and its connection are shown in Table 6-1.
Switch Function Microcontroller
RES When pressed, the board microcontroller is reset. RESETn, Pin8
SW1/BOOT* Connects to an IRQ 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, Pin31
(Port 1, pin 7)
SW2* Connects to an IRQ Interrupt input for user controls. INT2n, Pin28
(Port 6, pin 6)
SW3* Connects to an IRQ Interrupt input for user controls. ADTRGn_INT0n, Pin30
(Port 4, pin 5)
Connects to an ADTRG input for AD trigger controls.
Table 6-1: Switch Functions
*Refer to schematic for detailed connectivity information.
6.2. LEDs
There are six LEDs on the CPU 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 IO 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 3.1 26
LED1 Orange Port 3.3 16
LED2 Red Port 3.4 15
LED3 Red Port 3.6 25
Table 6-2: LED Port
6.3. Potentiometer
A single turn potentiometer is connected to AN8 (Port1.0) of the microcontroller. This may be used to vary the input analog voltage value to
this pin between VREF and Ground.
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 controllers ADC. Please see the device manual for details.
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