SH7713 Datasheet, PDF (491/904 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7700 Series

Section 12 Bus State Controller (BSC)
If the PCMCIA card is accessed as an I/O card in little endian mode, dynamic bus sizing for the
I/O bus can be achieved using the IOIS16 signal. If the IOIS16 signal is brought high in a word-
size I/O bus cycle while the bus width of area 6 is specified as 16 bits, the bus width is recognized
as 8 bits and data is accessed twice in 8-bit units in the I/O bus cycle to be executed.
The IOIS16 signal is sampled at the falling edge of CKIO in the Tpci0, Tpci0w, and Tpci1 cycles
when the TED[3:0] bits are specified as 1.5 cycles or more, and is reflected in the CE2 signal 1.5
cycles after the CKIO sampling point. The TED[3:0] bits must be specified appropriately to satisfy
the setup time from ICIORD and ICIOWR of the PC card to CEn.
Figure 12.44 shows the dynamic bus sizing basic timing.
Note that the IOIS16 signal is not supported in big endian mode. In the big endian mode, the
IOIS16 signal must be fixed low.
CKIO
A25 to A0
CExx
RD/WR
Read
Write
ICIORD
D15 to D0
ICIOWR
D15 to D0
BS
Tpci1
Tpci1w
Tpci1w
Tpci1w
Tpci2
Figure 12.42 Basic Timing for PCMCIA I/O Card Interface
Rev.1.50 Aug. 30, 2006 Page 451 of 860
REJ09B0288-0150