Renesas RX200 Series, Руководство пользователя

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Renesas Solution Starter Kit for RX23W 5. User Circuitry
R20UT4446EG0102 Rev. 1.02 Page 17 of 41
Jun 22, 20
5. User Circuitry
5.1 Reset Circuit
A reset control circuit is fitted to the CPU board to generate the required reset signal, and is triggered from the
RES switch. Refer to ‘RX23W Group User’s Manual: Hardware’ for details regarding the reset signal timing
requirements, and the CPU board schematics for information regarding the reset circuitry in use on the board.
5.2 Clock Circuit
A clock circuit is fitted to the CPU board to generate the required clock signal to drive the MCU, and
associated peripherals. Refer to ‘RX23W Group User’s Manual: Hardware’ Manual for details regarding the
clock signal requirements, and the CPU board schematics for information regarding the clock circuitry in use
on the CPU board. Details of the oscillators fitted to the board are listed in Table 5-1 below.
Table 5-1: Crystal
Crystal Function Default Placement Frequency Device Package
X1 RF/Main MCU crystal for RX23W *1 Fitted 32MHz Encapsulated, SMT
X2 Main(Reserve) MCU crystal for RX23W *1 Fitted 8MHz Encapsulated, SMT
X3 Real time Clock for RX23W Fitted 32.768kHz
*2
Encapsulated, SMT
*1
: If HOCO is selected as the MCU operating clock, the USB function cannot be used.
*2 : 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 five switches located on the CPU board. The function of each switch and its connection is shown in
Table 5-2 and Table 5-3
. For further information regarding switch connectivity, refer to the CPU board
schematics.
Table 5-2: Push Switch Connections
Switch Function
MCU
Signal (Port) Pin
RES When pressed, the microcontroller is reset. RES# B6
SW1
Connects to an ADTRG0 input for ADC controls. P07 C7
Connects to an IRQ1 input for user controls. P31 B4
SW2 Connects to an IRQ0 input for user controls. P30 A2
Table 5-3: DIP Switch Connections
Switch Function
MCU
Signal (Port) Pin
SW3 Pin 1 Refer to section 6.2 for the setting contents. MD/FINED B7
Pin 2 Refer to section 6.2 for the setting contents. PC7 F1
SW4 Pin 1 User switch. P45 E9
Pin 2 P46 E8
Pin 3 PB0 J6
Pin 4 PE4 J8