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

RSKRX111

5. User Circuitry

5.1

Reset Circuit

A reset control circuit is fitted to the RSK to generate the required reset signal, and is triggered from the RES
switch. Refer to the RX111 hardware manual for details regarding the reset signal timing requirements, and
the RSK schematics for information regarding the reset circuitry in use on the board.
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 RX111 Group Hardware Manual for details regarding the clock signal requirements,
and the RSKRX111 board schematics for information regarding the clock circuitry in use on the RSK. Details
of the oscillators fitted to the board are listed in Table 5-1 below.
Crystal
X1 Main MCU oscillator.
X2 RX111 Sub oscillator
X3 RL78/G1C Main oscillator
* The Sub clock oscillator drive circuit is low power to achieve excellent standby power consumption. The
Crystal and associated capacitors must have a capacitance equal or less than 6pF to ensure this oscillator is
accurate. The oscillator will function at higher loads, but operation to specification is not guaranteed.
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 an IRQ input for user controls.
SW2 Connects to an IRQ input for user controls.
SW3 Connects to an IRQ input for user controls. The switch is
also connected to an ADTRG input, and is used to trigger
AD conversions.
R20UT2193EG0200 Rev. 2.00
Apr 14, 2014
Function Default Placement
Fitted
Fitted
Fitted
Table 5-1: Oscillators
Function
Table 5-2: Switch Connections
5.
Frequency Device Package
16MHz Encapsulated, SMT
32.768kHz * Encapsulated, SMT
12MHz Encapsulated, SMT
MCU
Signal (Port)
RES#
IRQ0 (P30)
IRQ1 (P31)
IRQ4 (PE4)
ADTRG0# (PB0)
User Circuitry
Pin
7
4
5
47
39
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