gc80c520a CORERIVER Semiconductor, gc80c520a Datasheet - Page 56

• Manufacturer Part Number: gc80c520a
• Description: Midas1.0 Family Mask Rom/eprom/romless 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

The PWM0 and PWM1 registers operate as 8-bit or 6-bit incrementing counters. The counter values
increment until they reach to overflow. To operate the counter and the PWM block, set
PWM0CON[0]/PWM1CON[0] to 1. If PWM0CON[0]/PWM1CON[0] is cleared to 0, the counter will stop
and retain its value; when re-started, it will resume counting from the retained value. To clear the value of
the counter to 0, set the bits PWM0CON[1]/PWM1CON[1] to 1. The PWM supports two modes: an 8-bit
counter mode; a 6-bit counter and 2-bit extension mode. If PWM0CON[3] or PWM1OCN[3] is set to 1, a
PWM block operates in the 8-bit counter mode. Otherwise, it operates in (2+6)-bit mode.
The prescale factor of the input clock frequency for a PWM counter, is determined by the value of
PWM0CON[6:4] or PWM1CON[6:4]. The selectable input frequencies (F
F
6.2.6.1 Block Diagram
6.2.6.2 PWM components
The 8-bit PWM circuits consist of the following components:
OSC
/128 F
A 6-bit/8-bit comparator and a 2-bit extension effect implementation circuit
A 6-bit/8-bit duty data register (PWM0D/PWM1D/PWM0D[5:0]/PWM1D[5:0])
A 2-bit extension data register (PWM0D[7:6]/PWM1D[7:6])
OSC
/64, F
OSC
/32, F
OSC
7
(1/2/4/8/16/32/64/128)
8-bit Buffer
6
/16, F
PWM0D
PWM0 Counter
Figure 6-26 Functional block diagram
5
Clock Divide
4
F
OSC
OSC
3
F
/8, F
PWM
2
(2+6) bit
8-bit
1
OSC
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0
Comparator
/4, F
* PWM1 Block is same as PWM0 Block.
Overflow
PWM0CON[6:4]
OSC
Clear
Set
/2, and F
Generation
PWM0
Pulse
OSC
/1.
Functional Description
PWM0
Output
OSC
* prescale factor) are