HD6432621 Hitachi, HD6432621 Datasheet - Page 63

• Manufacturer Part Number: HD6432621
• Description: (HD64F262x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

Type
Operating
mode control
System
control
Interrupts
Address bus
Symbol
MD2 to
MD0
RES
STBY
BREQ
BREQO
BACK
FWE
NMI
IRQ5 to
IRQ0
A23 to A0
I/O
Input
Input
Input
Input
Output
Output
Input
Input
Input
Output
Pin Name
Mode pins
Reset input
Standby
Bus request
Bus request
output
Bus request
acknowledge
Flash write enable Pin for use by flash memory
Nonmaskable
interrupt
Interrupt request
5 to 0
Address bus
Function
These pins set the operating mode. The
relation between the settings of pins
MD2 to MD0 and the operating mode is
shown below. Inputs at these pins
should not be changed during
operation.
MD2
0
1
When this pin is driven low, the chip is
reset.
When this pin is driven low, a transition
is made to hardware standby mode.
Used by an external bus master to issue
a bus request to the chip.
External bus request signal used when
an internal bus master accesses
external space in the external bus-
released state.
Indicates that the bus has been
released to an external bus master.
Requests a nonmaskable interrupt. If
this pin is not used, it should be fixed
high.
These pins request a maskable
interrupt.
These pins output address signals.
MD1
0
1
0
1
MD0
0
1
0
1
0
1
0
1
Operating Mode
—
—
—
—
Mode 4
Mode 5
Mode 6
Mode 7
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