NEC PD754244 Network Card User Manual


 
CHAPTER 6 PERIPHERAL HARDWARE FUNCTION
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Users Manual U10676EJ3V0UM
6.4.3 Operation in PWM pulse generator mode (PWM mode)
In this mode, the timer counter (channel 2) is used as a PWM pulse generator.
The timer counter operates as an 8-bit PWM pulse generator.
When the timer counter (channel 2) is used as a PWM pulse generator, the timer counters (channel 0 and 1) can
be used as 8-bit timer counter.
(1) Register setting
In the PWM mode, the following five registers are used.
Timer counter mode register (TM2)
Timer counter control register (TC2)
Timer counter count register (T2)
Timer counter high-level period setting modulo register (TMOD2H)
Timer counter modulo register (TMOD2)
(a) Timer counter mode register (TM2)
In the PWM mode, set TM2 as shown in Figure 6-36 (for the format of TM2, refer to Figure 6-28 Format
of Timer Counter Mode Register (Channel 2)).
TM2 is manipulated by an 8-bit manipulation instruction. Bit 3 is a timer start command bit which can
be manipulated in 1-bit units and is automatically cleared to 0 when the timer starts operating.
TM2 is also cleared to 00H when the internal reset signal is asserted.