Renesas RX71M, Руководство пользователя, Страница: 17 / 72

RSK+RX71M 5. User Circuitry
R20UT3217EG0100 Rev. 1.00 Page 17 of 71
Jan 23, 2015
5. User Circuitry
5.1 Reset Circuit
A reset control circuit is fitted to the RSK+ to generate a reset signal from the RES switch. Refer to the RX71M
Group User’s Manual: Hardware 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 RX71M Group User’s Manual: Hardware and the RL78/G1C Group User’s Manual:
Hardware for details regarding the clock signal requirements, and the RSK+RX71M 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
Oscillator
Function
Default
Placement
Frequency Device Package
X1 Main MCU crystal for RX71M Fitted 24MHz Encapsulated, SMT
X2 Real time Clock for RX71M Fitted 32.768kHz Encapsulated, SMT
X3 Main MCU crystal for RL78/G1C Fitted 12MHz Encapsulated, SMT
X4 Crystal for Ethernet (MII) Fitted 25MHz Encapsulated, SMT
X5 Oscillator for Ethernet (RMII) Unfitted 50MHz Encapsulated, DIP half size
Table 5-1: Oscillators
* When evaluating RMII mode, it is necessary to mount the Oscillator X5. (Manufacture name: Epson, Model-
name: SG-8002DC).
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+ board schematics.
Switch Function
MCU
Signal (Port) Pin
RES When pressed, the microcontroller is reset. RES# 21
SW1 Connects to an IRQ input for user controls. IRQ5 (P15) 50
SW2 Connects to an IRQ input for user controls. IRQ2 (P12) 53
SW3 Connects to an ADTRG input for ADC controls.
(P07 can be used also as IRQ15)
ADTRG0n (P07) 176
Table 5-2: Switch Connections