EM78468
8-BIT Microcontroller
the counter and read preset value. The pre-scaler is set by IOC91 register. After an
interruption, it will auto reload the preset value.
4.2.9
IOCC0/CNT2PR (Counter 2 Preset Register)
(Address: 0Ch, Bit 0 of R5 = “0”)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7 ~ Bit 0: All are Counter 2 buffer that user can read and write. The Counter 2 is an
8-bit down-count timer with 8-bit pre-scaler that is used as this register to preset the
counter and read preset value. The pre-scaler is set by IOC91 register. After an
interruption, it will reload the preset value.
When IR output is enabled, this control register can obtain carrier frequency output.
If the Counter 2 clock source is equal to FT –
FT
Carrier frequency (Fcarrier) =
2 * (preset _ value +1) * prescaler
4.2.10 IOCD0/HPWTPR (High-Pulse Width Timer Preset Register)
(Address: 0Dh, Bit 0 of R5 = “0”)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7 ~ Bit 0: All are high-pulse width timer buffer that user can read and write.
High-pulse width timer preset register is an eight-bit down-count timer with 8-bit
pre-scaler that is used as IOCD0 to preset the counter and read preset value. The
pre-scaler is set by IOCA1 register. After an interruption, it will reload the preset value.
For PWM or IR application, this control register is set as high pulse width.
If the high-pulse width timer source clock is FT –
prescaler * (preset _ value +1)
High pulse time =
FT
4.2.11 IOCE0/LPWTPR (Low-Pulse Width Timer Preset Register)
(Address: 0Eh, Bit 0 of R5 = “0”)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7 ~ Bit 0: All are low-pulse width timer buffer that user can read and write. Low-pulse
width timer preset is an eight-bit down-count timer with 8-bit pre-scaler that is used as
IOCE0 to preset the counter and read preset value. The pre-scaler is set by IOCA1
register. After an interruption, it will reload the preset value.
For PWM or IR application, this control register is set as low pulse width.
If the low-pulse width timer source clock is FT –
Product Specification (V1.1) 04.11.2005
(This specification is subject to change without further notice)
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