SH7706 Datasheet, PDF (222/749 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family/SH7700 Series

Section 8 Bus State Controller (BSC)
8.4.1 Bus Control Register 1 (BCR1)
Bus control register 1 (BCR1) is a 16-bit read/write register that sets the functions and bus cycle
state for each area. It is initialized to H'0000 by a power-on reset, but is not initialized by a manual
reset or by standby mode. Do not access external memory outside area 0 until BCR1 register
initialization is complete.
Bit Bit Name Initial Value R/W Description
15 PULA
0
R/W Pin A25 to A0 Pull-Up
Specifies whether or not pins A25 to A0 are pulled up
for 4 cycles immediately after BACK is asserted.
0: Not pulled up
1: Pulled up
14 PULD
0
R/W Pin D31 to D0 Pull-Up
Specifies whether or not pins D31 to D0 are pulled up
when not in use.
0: Not pulled up
1: Pulled up
13 HIZMEM 0
R/W Hi-Z memory control
Specifies the state of A25 to 0, BS, CS, RD/WR,
WE/DQM, RD, CE2A, CE2B and DRAK0/1 in standby
mode.
0: High-impedance state in standby mode.
1: Driven in standby mode.
12 HIZCNT 0
R/W Hi-Z Control
Specifies the state of the RAS and the CAS signals at
standby and bus right release.
0: High-impedance state at standby and bus right
release.
11 ENDIAN 0/1^*1
1: Driven at standby and bus right release.
R
Endian Flag
Samples the value of the external pin designating
endian upon a power-on reset. Endian for all physical
spaces is decided by this bit, which is read-only.
0: (On reset) Endian setting external pin (MD5) is low.
Indicates the SH7706 is set as big endian.
1: (On reset) Endian setting external pin (MD5) is high.
Indicates the SH7706 is set as little endian.
Rev. 5.00 May 29, 2006 page 174 of 698
REJ09B0146-0500