sh6622a SinoWealth Micro-Electronics Corp. Ltd, sh6622a Datasheet - Page 10

• Manufacturer Part Number: sh6622a
• Description: Mask 4-bit Microcontroller
• Manufacturer: SinoWealth Micro-Electronics Corp. Ltd

5. Port Interrupt
PBC interrupt (PORTB & PORTC, 8bits) is falling edge active. It means that if an interrupt request (IEx is set to 1 and one port
bit is high go low) is been touched and that the condition is the other port bits are high level. Only input port can generate
interrupt.
6. System Clock and Oscillator
System clock generator produces the basic clock pulses that provide the system clock with CPU and peripherals.
Instruction cycle time
(1) 4/32.768KHz (≈ 122us) for 32.768KHz system clock
(2) 4/4MHz (≈ 1us) for 4MHz system clock
Oscillator
(1) Crystal oscillator: 32.768KHz - 4MHz.
(2) Ceramic resonator: 400KHz - 4MHz.
(3) RC oscillator: 400KHz - 4MHz.
(4) External input clock: 30KHz - 4MHz.
OSCO
OSCI
OSCI
OSCO
Fosc/4
32.768K ~ 4MHz
400K ~ 4MHz
V
C1
Ceramic
Crystal
External clock source
C2
C1
DD
C2
R
10
C1, C2 Setting :
Crystal 32.768KHz :
C1, C2 < 56p (V
C1, C2 < 56p (V
Crystal 4MHz :
C1, C2 < 33p (V
C1, C2 < 10p (V
C1, C2 Setting :
Ceramic 400KHz :
20p < C1, C2 < 470p (V
20p < C1, C2 < 150p (V
Ceramic 4MHz :
20p < C1, C2 < 100p (V
C1, C2 < 10p (V
DD
DD
DD
DD
DD
= 5V);
= 3V).
= 5V);
= 3V).
= 3V).
DD
DD
DD
= 5V);
= 3V).
= 5V);
SH6622A