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FUJITSU F2MCTM-16LX User Manual

Page 303

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CHAPTER 16 8-/16-BIT PPG TIMER

Details of pins in block diagram

Table 16.2-1 lists the actual pin names and interrupt request numbers of the 8-/16-bit PPG timer.

PPG operation mode control register C (PPGCC)

This register enables or disables operation of the 8-/16-bit PPG timer, pin output and an underflow

interrupt. It also indicates the occurrence of an underflow.

PPGC/D count clock select register (PPGCD)

This register sets the count clock of the 8-/16-bit PPG timer and switching the output pin between PPGC

and PPGD.

PPGC reload registers (PRLHC, PRLLC)

These registers set the High width or Low width of the output pulse. The values set in these registers are

reloaded to the PPGC down counter (PCNTC) when the 8-/16-bit PPG timer is started.

PPGC down counter (PCNTC)

This counter is an 8-bit down counter that alternately reloads the values set in the PPGC reload registers

(PRLHC and PRLLC) to decrement. When an underflow occurs, the pin output is inverted. The 2-channel

PPG down counters (PPGC and PPGD) can also be concatenated for use as a single-channel 16-bit PPG

down counter.

PPGC temporary buffer (PRLBHC)

This buffer prevents deviation of the output pulse width caused at writing to the PPG reload registers

(PRLHC and PRLLC). This buffer stores the PRLHC value temporarily and enables it in synchronization

with the timing of writing to the PRLLC.

Reload register L/H selector

This selector detects the current pin output level to select which register value, Low reload register

(PRLLC) or High reload register (PRLHC), should be reloaded to the PPGC down counter.

Count clock selector

This selector selects the count clock to be inputted to the PPGC down counter from five frequency-divided

clocks of the machine clock or the frequency-divided clocks of the timebase timer.

PPG output control circuit

This circuit inverts the pin output level and the output when an underflow occurs.

Table 16.2-1 Pins and Interrupt Request Numbers in Block Diagram

Channel

Output Pin

Interrupt Request

Number

PPG:REV=0

PPG:REV=1

PPGC

P66 / PPGC

P22 / PPGD

#23 (17

H

)

PPGD

P22 / PPGD

P66 / PPGC

PPGE

P67/ PPGE

P23 / PPGF

#24 (18

H

)

PPGF

P23/ PPGF

P67 / PPGE