User Circuitry; Reset Circuit; Clock Circuit; Switches - Renesas RL78 Series User Manual

RSKRL78G1G

5. User Circuitry

5.1

Reset Circuit

A reset control circuit is not fitted to the RSK, as the MCU is capable of voltage and power-on detection.
Resets are handled internally, and the reset switch is connected directly to the RESET pin on the MCU.
5.2

Clock Circuit

A clock circuit is fitted to the RSK to generate the required clock signal to drive the MCU, and associated
peripherals. Refer to the RL78/G1G Group Hardware Manual for details regarding the clock signal
requirements, and the RSKRL78
the RSK. Details of the oscillators fitted to the board are listed in Table 5-1 below.
Crystal
X1 Main MCU crystal for RL78/G1G
X2 Main MCU crystal for RL78/G1C
5.3

Switches

There are four switches located on the RSK board. The function of each switch and its connection is shown in
Table 5-2. For further information regarding switch connectivity, refer to the RSK schematics.
Switch
RES When pressed, the microcontroller is reset
SW1 Connects to a key return input for user controls
SW2 Connects to a general purpose I/O for user controls
SW3 Connects to a general purpose I/O for user controls
5.4

LEDs

There are five LEDs on the RSK. The function of each LED, its colour, and its connections are shown in Table
5-3.
LED Colour
POWER Green
LED0 Green
LED1 Orange
LED2 Red
LED3 Red
R20UT3022EG0100 Rev. 1.00
Jan 15, 2015
board schematics for information regarding the clock circuitry in use on
/G1G
Function
Fitted
Fitted
Table 5-1: Oscillators
Function
Table 5-2: Switch Connections
Indicates the power status
User operated LED
User operated LED
User operated LED
User operated LED
Table 5-3: LED Connections
Default Placement
20MHz
12MHz
Function
5.
Frequency Device Package
Encapsulated, SMT
Encapsulated, SMT
MCU
Port
RESETn
KR0(P70)
P124
P123
Port
-
P41
P63
P72
P73
User Circuitry
Pin
3
20
4
5
MCU
Pin
-
1
15
18
17
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