UPD784035YGC NEC, UPD784035YGC Datasheet - Page 56

• Manufacturer Part Number: UPD784035YGC
• Description: 16-/8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: NEC

11. RESET FUNCTION
system can be reset and started from any address.
circuit is a sampling circuit by analog delay.
ON reset operation.
56
Internal reset signal
Internal reset signal
When the low level is input to the RESET pin, the internal hardware is initialized (reset status).
When the RESET pin goes high, the following data are set to the program counter (PC).
• Lower 8 bits of PC: contents of address 0000H
• Middle 8 bits of PC: contents of address 0001H
• Higher 4 bits of PC: 0
Program execution is started from a branch destination address which is the contents of the PC. Therefore, the
Set the contents of each register by program as necessary.
The RESET input circuit has a noise reduction circuit to prevent malfunctioning due to noise. This noise reduction
Assert the RESET signal active until the oscillation stabilization time (approx. 40 ms) elapses to execute a power-
RESET
(input)
RESET
(input)
V
DD
Delay
Oscillation stabilization time
Figure 11-2. Power-ON Reset Operation
Figure 11-1. Accepting RESET Signal
Delay
Reset starts
PD784035Y, 784036Y, 784037Y, 784038Y
Delay
Reset ends
Initialize PC
Delay
Reset ends
Initialize PC
Executes instruction at
reset start address
Executes instruction at
reset start address