UPD65 NEC [NEC], UPD65 Datasheet - Page 26

• Manufacturer Part Number: UPD65
• Description: 4-BIT SINGLE-CHIP MICROCONTROLLER FOR INFRARED REMOTE CONTROL TRANSMISSION
• Manufacturer: NEC [NEC]

6. RESET
26
PC (11 bits)
SP (1 bit)
Data
memory
Accumulator (A)
Status flag (F)
Carry flag (CY)
Timer (10 bits)
Port register
Control register P3
The system reset takes effect by means of the causes as follows:
• When the POC circuit has detected low-power voltage
• When the operand value is illegal or does not satisfy the precondition when the HALT instruction is executed
• When the accumulator is 0H when the RLZ instruction is executed
• When stack pointer overflows or underflows
Notes 1. The following resets are available.
Hardware
2. Refers to the value by the K
R1-RF
R0 = DP
• Reset when executing the HALT instruction (when the operand value is illegal or does not satisfy
• Reset when executing the RLZ instruction (when A = 0)
• Reset by stack pointer’s overflow or underflow
In order to prevent malfunction, be sure to input a low level to more than one of pins K
POC is released due to supply voltage startup.
the precondition)
P0
P1
P4
• Resetting by Internal POC Circuit in Operation
• Resetting by Other Factors
000H
0B
000H
Undefined
Undefined
0B
0B
000H
FFH
03H
26H
11 1B
Note 2
Table 6-1. Hardware Statuses after Reset
I
or S
Data Sheet U14380EJ2V0DS00
Note 1
2
pin status.
• Resetting by the Internal POC Circuit during
Previous status retained
STANDBY Mode
I0
to K
PD64A, 65
I3
when