134
7.1.3
Pin Configuration
Table 7-1 summarizes the pins of the bus controller.
Table 7-1
Bus Controller Pins
Name
Symbol
I/O
Function
Address strobe
AS
Output
Strobe signal indicating that address output on address
bus is enabled.
Read
RD
Output
Strobe signal indicating that external space is being
read.
High write/
write enable
HWR
Output
Strobe signal indicating that external space is to be
written, and upper half (D15 to D8) of data bus is
enabled.
Low write
LWR
Output
Strobe signal indicating that external space is to be
written, and lower half (D7 to D0) of data bus is enabled.
Chip select 0
CS0
Output
Strobe signal showing selection of area 0
Chip select 1
CS1
Output
Strobe signal showing selection of area 1
Chip select 2/row
address strobe 2
CS2
Output
Strobe signal showing selection of area 2.
When area 2 is allocated to DRAM space, this is the row
address strobe signal for DRAM.
When areas 2 to 5 are contiguous DRAM space, this is
the row address strobe signal for DRAM.
Chip select 3/row
address strobe 3
CS3
/
OE
Output
Strobe signal showing selection of area 3.
When area 3 is allocated to DRAM space, this is the row
address strobe signal for DRAM.
When only area 2 is allocated to DRAM space, or when
areas 2 to 5 are contiguous DRAM space, this is output
enable signal.
Chip select 4/row
address strobe 4
CS4
Output
Strobe signal showing selection of area 4.
When area 4 is allocated to DRAM space, this is the row
address strobe signal for DRAM.
Chip select 5/row
address strobe 5
CS5
Output
Strobe signal showing selection of area 5.
When area 5 is allocated to DRAM space, this is the row
address strobe signal for DRAM.
Chip select 6
CS6
Output
Strobe signal showing selection of area 6.
Chip select 7
CS7
Output
Strobe signal showing selection of area 7.
Upper column
address strobe
CAS
Output
2 CAS method DRAM upper column address strobe
signal
Lower column
strobe
LCAS
Output
DRAM lower column address strobe signal
Содержание H8S/2631
Страница 28: ...xviii Appendix G Package Dimensions 1154 ...
Страница 341: ...316 Transfer SAR or DAR DAR or SAR Block area First block Nth block Figure 9 8 Memory Mapping in Block Transfer Mode ...
Страница 918: ...905 ø DREQ0 DREQ1 tDRQS tDRQH Figure 25 19 DMAC DREQ Input Timing ...
Страница 955: ...943 A 2 Instruction Codes Table A 2 shows the instruction codes ...