SH7708 Datasheet, PDF (222/633 Pages) Renesas Technology Corp – SuperH™ RISC engine

Bit 2n + 1: AnSZ1 Bit 2n: AnSZ0
0
0
1
1
0
1
0
0
1
1
0
1
Bit 0: PORTEN
0
1
Description
Reserved (not settable)
Byte (8-bit) size
Word (16-bit) size
Longword (32-bit) size
(Initial value)
Reserved (not settable)
Byte (8-bit) size
Word (16-bit) size
Reserved (not settable)
Bit 0—Port Function Enable (PORTEN): Designates whether to use the D23–D16 pins as an 8-bit
port. When using this function set the bus widths to word or byte in all areas.
Bit 0: PORTEN
0
1
Description
D23–D16 are not used as a port.
D23–D16 are used as a port.
(Initial value)
10.2.3 Wait State Control Register 1 (WCR1)
Wait state control register 1 (WCR1) is a 16-bit read/write register that specifies the number of
idle (wait) state cycles inserted for each area. For some memories, the drive of the data bus may
not be turned off quickly even when the read signal from the external device is turned off. This
can result in conflicts between data buses when consecutive memory accesses are to different
memories or when a write immediately follows a memory read. The SH7708 Series automatically
inserts idle states equal to the number set in WCR1 in those cases.
WCR1 is initialized to H'3FFF by a power-on reset. It is not initialized by a manual reset or in
standby mode, but retains its contents.
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