HD6417615 Hitachi Semiconductor, HD6417615 Datasheet - Page 34

• Manufacturer Part Number: HD6417615
• Description: Hardware Manual
• Manufacturer: Hitachi Semiconductor

Table 1.2
Type
System
control
Operating
mode
Interrupts
Bus control
16
Pin Functions (cont)
Symbol
RES
WDTOVF
BGR
BRLS
MD0–MD4
NMI
IRL3–IRL0
IVECF
BS
CS4–CS0
WAIT
RD
RAS
I/O
Input
Output
Output
Input
Input
Input
Input
Output
Output
Output
Input
Output
Output
Name
Reset
Watchdog
timer overflow
Bus grant
Bus release
Mode setting
Nonmaskable
interrupt
External
interrupt
request input
0 to 3
Interrupt
vector fetch
cycle
Bus cycle
start
Chip select
0 to 4
Wait
Read
Row address
strobe
Function
When RES = 0 and NMI = 1, the chip
enters the power-on reset state. When
RES = 0 and NMI = 0, the chip enters the
manual reset state
Counter overflow signal output in
watchdog timer mode
Indicates that the bus has been released
to an external device. The device that
output the BRLS signal recognizes that
the bus has been acquired when it
receives the BGR signal
Driven low when an external device
requests release of the bus
The operating mode is specified by the
levels at these pins
Inputs the nonmaskable interrupt request
signal
These pins input maskable interrupt
request signals
Indicates an external vector read cycle
Signal indicating the start of a bus cycle
Asserted every data cycle in burst
transfer
Chip select signals indicating the area
being accessed
Wait state request signal
Strobe signal indicating a read cycle
DRAM/synchronous DRAM RAS signal