HT66F4530 Datasheet, PDF (88/224 Pages) Holtek Semiconductor Inc – A/D Flash MCU with Dual Operational Amplifiers

HT66F4530/HT66F4540/HT66F4550
A/D Flash MCU with Dual Operational Amplifiers
Timer Modules – TM
One of the most fundamental functions in any microcontroller these devices is the ability to
control and measure time. To implement time related functions each device includes several Timer
Modules, abbreviated to the name TM. The TMs are multi-purpose timing units and serve to provide
operations such as Timer/Counter, Input Capture, Compare Match Output and Single Pulse Output
as well as being the functional unit for the generation of PWM signals. Each of the TMs has two
individual interrupts. The addition of input and output pins for each TM ensures that users are
provided with timing units with a wide and flexible range of features.
The common features of the different TM types are described here with more detailed information
provided in the individual Standard and Periodic TM sections.
Introduction
These devices contain up to four TMs and each individual TM can be categorised as a certain type,
namely Standard Type TM or Periodic Type TM. Although similar in nature, the different TM types
vary in their feature complexity. The common features to all of the Standard and Periodic TMs
will be described in this section. The detailed operation regarding each of the TM types will be
described in separate sections. The main features and differences between the two types of TMs are
summarised in the accompanying table.
Function
Timer/Counter
Input Capture
Compare Match Output
PWM Channels
Single Pulse Output
PWM Alignment
PWM Adjustment Period & Duty
STM
√
√
√
1
1
Edge
Duty or Period
PTM
√
√
√
1
1
Edge
Duty or Period
TM Function Summary
Device
HT66F4530
HT66F4540
HT66F4550
STM
10-bit STM0
10-bit STM0
10-bit STM0
10-bit STM1
PTM
10-bit PTM0
10-bit PTM0
10-bit PTM1
10-bit PTM0
10-bit PTM1
TM Name/Type Reference
TM Operation
The different types of TM offer a diverse range of functions, from simple timing operations to
PWM signal generation. The key to understanding how the TM operates is to see it in terms of
a free running counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running counter has the same value as the pre-programmed comparator,
known as a compare match situation, a TM interrupt signal will be generated which can clear the
counter and perhaps also change the condition of the TM output pin. The internal TM counter is
driven by a user selectable clock source, which can be an internal clock or an external pin.
Rev. 1.00
88
December 21, 2016