Section 6 Bus Controller (BSC)
Rev. 1.00 Mar. 12, 2008 Page 152 of 1178
REJ09B0403-0100
6.6
Burst ROM Interface
In this LSI, the external address space can be designated as the burst ROM space by the BRSTRM
bit in BCR, and the burst ROM interface enabled. Consecutive burst accesses of a maximum four
or eight words can be performed only during CPU instruction fetch. 1 or 2 states can be selected
for burst ROM access.
6.6.1
Basic Operation Timing
The number of access states in the initial cycle (full access) of the burst ROM interface is
determined by the AST bit in WSCR. When the AST bit is set to 1, wait states can be inserted. 1
or 2 states can be selected for burst access according to the setting of the BRSTS1 bit in BCR.
Wait states cannot be inserted in a burst cycle. Burst accesses of a maximum four words is
performed when the BRSTS0 bit in BCR is cleared to 0, and burst accesses of a maximum eight
words is performed when the BRSTS0 bit in BCR is set to 1.
The basic access timing for the burst ROM space is shown in figures 6.30 and 6.31.
T
1
Address bus
φ
AS
/
IOS
Data bus
T
2
T
3
T
1
T
2
T
1
Full access
T
2
RD
Burst access
Only lower address changes
Read data
Read data
Read data
(IOSE = 0)
Figure 6.30 Access Timing Example in Burst ROM Space (AST = BRSTS1 = 1)
Содержание H8S Family
Страница 2: ...Rev 1 00 Mar 12 2008 Page ii of xIviii...
Страница 8: ...Rev 1 00 Mar 12 2008 Page viii of xIviii...
Страница 28: ...Rev 1 00 Mar 12 2008 Page xxviii of xIviii...
Страница 48: ...Rev 1 00 Mar 12 2008 Page xlviii of xIviii...
Страница 70: ...Section 1 Overview Rev 1 00 Mar 12 2008 Page 22 of 1178 REJ09B0403 0100...
Страница 108: ...Section 2 CPU Rev 1 00 Mar 12 2008 Page 60 of 1178 REJ09B0403 0100...
Страница 116: ...Section 3 MCU Operating Modes Rev 1 00 Mar 12 2008 Page 68 of 1178 REJ09B0403 0100...
Страница 152: ...Section 5 Interrupt Controller Rev 1 00 Mar 12 2008 Page 104 of 1178 REJ09B0403 0100...
Страница 206: ...Section 6 Bus Controller BSC Rev 1 00 Mar 12 2008 Page 158 of 1178 REJ09B0403 0100...
Страница 420: ...Section 9 14 Bit PWM Timer PWMX Rev 1 00 Mar 12 2008 Page 372 of 1178 REJ09B0403 0100...
Страница 476: ...Section 12 Watchdog Timer WDT Rev 1 00 Mar 12 2008 Page 428 of 1178 REJ09B0403 0100...
Страница 552: ...Section 14 CRC Operation Circuit CRC Rev 1 00 Mar 12 2008 Page 504 of 1178 REJ09B0403 0100...
Страница 588: ...Section 15 Serial Communication Interface with FIFO SCIF Rev 1 00 Mar 12 2008 Page 540 of 1178 REJ09B0403 0100...
Страница 632: ...Section 17 Synchronous Serial Communication Unit SSU Rev 1 00 Mar 12 2008 Page 584 of 1178 REJ09B0403 0100...
Страница 712: ...Section 18 I2 C Bus Interface IIC Rev 1 00 Mar 12 2008 Page 664 of 1178 REJ09B0403 0100...
Страница 804: ...Section 19 LPC Interface LPC Rev 1 00 Mar 12 2008 Page 756 of 1178 REJ09B0403 0100...
Страница 838: ...Section 20 Ethernet Controller EtherC Rev 1 00 Mar 12 2008 Page 790 of 1178 REJ09B0403 0100...
Страница 964: ...Section 24 RAM Rev 1 00 Mar 12 2008 Page 916 of 1178 REJ09B0403 0100...
Страница 1066: ...Section 25 Flash Memory Rev 1 00 Mar 12 2008 Page 1018 of 1178 REJ09B0403 0100...
Страница 1098: ...Section 26 Boundary Scan JTAG Rev 1 00 Mar 12 2008 Page 1050 of 1178 REJ09B0403 0100...
Страница 1168: ...Section 30 Platform Environment Control Interface PECI Rev 1 00 Mar 12 2008 Page 1120 of 1178 REJ09B0403 0100...
Страница 1226: ...Rev 1 00 Mar 12 2008 Page 1178 of 1178 REJ09B0403 0100...
Страница 1229: ......
Страница 1230: ...H8S 2472 Group H8S 2462 Group Hardware Manual...