Rev. 3.0, 04/02, page 327 of 1064
Bits 2n + 1, 2n—Area n (1 to 6) Bus Width Specification (AnSZ1, AnSZ0): These bits specify
the bus width of area n (n = 1 to 6).
(Bit 0): PORTEN
Bit 2n + 1: AnSZ1
Bit 2n: AnSZ0
Description
0
0
0
Reserved (Setting prohibited)
1
Bus width is 8 bits
1
0
Bus width is 16 bits
1
Bus width is 32 bits
(Initial value)
1
0
0
Reserved (Setting prohibited)
1
Bus width is 8 bits
1
0
Bus width is 16 bits
1
Bus width is 32 bits
Bit 1—Reserved: This bit is always read as 0, and should only be written with 0.
Bit 0—Port Function Enable (PORTEN): Specifies whether pins AD31 to AD0 are used as a
32-bit port. However, select PCI-disable mode when using this function.
Bit 0: PORTEN
Description
0
AD31 to AD0 are not used as a port
(Initial value)
1
AD31 to AD0 are used as a port
13.2.3
Bus Control Register 3 (BCR3) (SH7751R Only)
Bus control register 3 (BCR3) is a 16-bit readable/writable register that specifies the selection of
either the MPX interface or the SRAM interface and specifies the burst length when the
synchronous DRAM interface is used.
BCR3 is initialized to H'0000 by a power-on reset, but is not initialized by a manual reset or in
standby mode. No external memory space other than area 0 should be accessed before register
initialization has been completed.
Summary of Contents for SH7751
Page 39: ...Rev 3 0 04 02 page xxxviii of xxxviii ...
Page 89: ...Rev 3 0 04 02 page 50 of 1064 ...
Page 157: ...Rev 3 0 04 02 page 118 of 1064 ...
Page 193: ...Rev 3 0 04 02 page 154 of 1064 ...
Page 225: ...Rev 3 0 04 02 page 186 of 1064 ...
Page 253: ...Rev 3 0 04 02 page 214 of 1064 ...
Page 301: ...Rev 3 0 04 02 page 262 of 1064 ...
Page 343: ...Rev 3 0 04 02 page 304 of 1064 ...
Page 607: ...Rev 3 0 04 02 page 568 of 1064 ...
Page 671: ...Rev 3 0 04 02 page 632 of 1064 ...
Page 745: ...Rev 3 0 04 02 page 706 of 1064 ...
Page 767: ...Rev 3 0 04 02 page 728 of 1064 ...
Page 1061: ...Rev 3 0 04 02 page 1022 of 1064 NMI tNMIL tNMIH Figure 23 69 NMI Input Timing ...
Page 1069: ...Rev 3 0 04 02 page 1030 of 1064 ...
Page 1103: ...Rev 3 0 04 02 page 1064 of 1064 ...