Datasheet

R01DS0063EJ0120 Rev.1.20 Page 20 of 95
Feb 6, 2013
R32C/116 Group 1. Overview
Note:
1. Pins
BC2/D1, WR2, WR3, BC2, and BC3 are available in the 144-pin package only.
Table 1.15 Pin Definitions and Functions (2/4)
Function Symbol I/O Description
Bus control pins
BC0/D0, BC2/D1
(1)
I/O
Output of byte control (
BC0 and BC2) and input/output of
data (D0 and D1) by time-division while accessing an
external memory space with multiplexed bus
CS0 to CS3 O Chip select output
WR0/WR1/WR2/
WR3,
WR/BC0/BC1/
BC2/BC3,
RD
(1)
O
Output of write, byte control, and read signals. Either
WRx
or
WR and BCx can be selected by a program.
Data is read when
RD is low.
• When
WR0, WR1, WR2, WR3, and RD are selected,
data is written to the following address:
4n+0, when
WR0 is low
4n+1, when
WR1 is low
4n+2, when
WR2 is low
4n+3, when
WR3 is low
on 32-bit external data bus
or
an even address, when
WR0 is low
an odd address, when
WR1 is low
on 16-bit external data bus
• When
WR, BC0, BC1, BC2, BC3, and RD are selected,
data is written, when
WR is low
and
the following address is accessed:
4n+0, when
BC0 is low
4n+1, when
BC1 is low
4n+2, when
BC2 is low
4n+3, when
BC3 is low
on 32-bit external data bus
or
an even address, when
BC0 is low
an odd address, when
BC1 is low
on 16-bit external data bus
ALE O Latch enable signal in multiplexed bus format
HOLD I The MCU is in a hold state while this pin is held low
HLDA O This pin is driven low while the MCU is held in a hold state
RDY
I
Bus cycle is extended by the CPU if this pin is low on the
falling edge of BCLK