Renesas M16C Series User Manual

Timer A
M30240 Group
Rev.1.00 Sep 24, 2003 Page 74 of 360
1.2.21.4 Pulse-width modulation (PWM) mode
In this mode, the timer outputs pulses of a given width in succession (See Table 1.22 ). In this mode,
the counter functions as either a 16-bit pulse-width modulator or an 8-bit pulse-width modulator. Figure
1.67 shows an example of how a 16-bit pulse-width modulator operates. Figure 1.68 shows the Timer
Ai mode register in pulse-width modulation mode. Figure 1.69 shows the example of how an 8-bit
pulse width modulator operates.
Figure 1.67: Example of how a 16-bit pulse-width modulator operates
Table 1.22: Timer specifications in pulse-width modulation mode
Item Specification
Count source f1, f8, f32
Count operation
•The timer counts down (operating as an 8-bit or a 16-bit pulse-width modulator)
•The timer reloads a new count at a rising edge of PWM pulse and continues counting
• The timer is not affected by a trigger that occurs when counting
16-bit PWM
•High level width n / f
i
n: Set value
•Cycle time (2
16
-1) / f
i
fixed
8-bit PWM
•High level width n (m+1) /f
i
n: values set to timer Ai register’s high-order address
•Cycle time (2
8
-1) (m+1) /f
i
m: values set to timer Ai register’s low-order address
Count start condition
•External trigger is input
•The timer overflows
•The count start flag is set (= 1)
Count stop condition •The count start flag is reset (= 0)
Interrupt request
generation timing
PWM pulse goes “L”
TAi
IN
pin function Programmable I/O port or trigger input
TAi
OUT
pin function Pulse output
Read from timer When Timer Ai register is read, it indicates an indeterminate value
Write to timer
•When counting is stopped and a value is written to Timer Ai register, it is written to both
reload register and the counter
•When counting in progress and a value is written to Timer A register, it is written to only
reload register to be transferred to the counter at next reload timer.
1 / f i X (2 – 1)
16
Count source
TA
i IN pin
input signal
PWM pulse output
from TA
iOUT pin
Condition : Reload register = 0003 16 , when external trigger
(rising
edge of TA iIN pin input signal) is selected
Trigger is not generated by this signal
“H”
“H”
“L”
“L”
Timer Ai interrupt
request bit
“1”
“0”
Cleared to “0” when interrupt request is accepted, or cleared by software
f i : Frequency of count source
(f
1 , f 8 , f 32 )
16
to FFFE 16
1 / f i X n
Note: n = 0000

Renesas M16C Series Specifications

General

Architecture	16-bit
Core	M16C
Instruction Set Architecture	CISC
Flash Memory	Up to 512 KB
Operating Voltage	2.7V to 5.5V
Operating Temperature Range	-40°C to +85°C
Package Types	LQFP, QFP
Timers	Multiple 16-bit timers
ADC	10-bit
Communication Interfaces	UART, SPI, I2C
Interrupts	Multiple interrupt sources

Summary

Chapter 1: Hardware

1.1 Description

Overview of the M30240 group as a single-chip USB peripheral microcontroller based on M16C family.

1.1.1 Features

Lists the key features of the M30240 group, including CPU, USB capabilities, memory, voltage, and peripherals.

1.1.3 Pin Configuration

Shows the pin configuration (top view) of the M30240 group, detailing each pin's name, I/O, and basic function.

1.1.4 Block Diagram

Presents a block diagram illustrating the internal structure and major components of the M30240 group.

1.1.5 Performance outline

Details the performance specifications of the M30240 group, including instruction count, memory capacity, and I/O ports.

1.1.6 Pin Description

Provides a detailed description of each pin of the M30240 microcontroller, including its name, I/O type, and functions.

CHAPTER 2: PERIPHERAL FUNCTIONS USAGE

2.1 Protect

Explains the protect function to prevent unintended changes to important registers when a program runs away.

2.2 Timer A

Provides an overview and detailed operation modes of the 16-bit Timer A, including timer, event counter, and PWM modes.

2.3 Timer B

Details the operation and registers of Timer B, a 16-bit timer that operates only in timer mode.

2.4 Clock-Synchronous Serial I/O

Explains clock-synchronous serial communication, including transmission/reception formats, transfer rates, and error detection.

2.5 Clock-Asynchronous Serial I/O (UART)

Covers UART operations, including transmission/reception formats, transfer rates, error detection, and functions like SIM interface compliance.

2.6 A-D Converter

Describes the A-D converter, its modes of operation, conversion clock, conversion time, and related registers.

2.7 DMAC

Explains the DMAC (Direct Memory Access Controller) for data transfer between memory and peripherals without CPU intervention.

2.10 Address Match Interrupt

Explains the address match interrupt functionality for simplified debugging, including enable/disable and timing.

2.11 Key-Input Interrupt

Describes the key-input interrupt, which is generated by falling edges on Port 0 or Port 1 pins used as input.

2.12 Power Control

Explains power control modes (Normal, Wait, Stop) for reducing CPU power consumption by stopping oscillators or clocks.

2.13 Programmable I/O Ports

Details the programmable I/O ports, including direction registers, port registers, pull-up control, and high drive capacity.

Chapter 3 Universal Serial Bus

3.1 Frequency Synthesizer

Explains how to set up and use the frequency synthesizer to generate the 48MHz clock for USB and DC-DC converter power.

3.2 Universal Serial Bus

Provides an overview of the Universal Serial Bus (USB) features, including specification compatibility, error handling, and transfer types.

3.2.2 USB Related Registers

Lists and describes USB-related registers for controlling USB functionality, including control, status, and enable registers.

3.2.7 USB Interrupts

Details the types of USB interrupts (Function, Reset, Resume, SOF, Suspend) and their handling via enable flags and priority levels.

3.2.8 USB Function Control Unit Initialization

Outlines the initialization routine for the USB Function Control Unit, including frequency synthesizer setup and endpoint initialization.

3.2.9 USB Control Transfers and SET_ADDRESS Request

Explains USB control transfers, the SET_ADDRESS request, and procedures for setting the device address.

Chapter 4 Interrupts

4.1 Overview of Interrupts

Provides an overview of interrupt types, including software, hardware, special, and peripheral I/O interrupts.

4.1.1 Type of Interrupts

Classifies interrupts into maskable and non-maskable types, detailing software and hardware interrupt categories.

4.1.2 Interrupt Vector Tables

Describes interrupt vector tables, including fixed and variable types, and lists interrupts assigned to fixed vector tables.

4.1.3 Interrupt Control

Explains interrupt control registers, interrupt request bits, enable flags, and priority levels for managing interrupts.

4.1.4 Interrupt Sequence

Details the sequence of operations when an interrupt occurs, including saving registers and processor control flow.

4.1.5 Multiple Interrupts

Explains how multiple interrupts are handled, including priority levels and interrupt acceptance conditions.

Chapter 5 Built-in PROM Version

5.1 Built-in PROM Version

Introduces the built-in PROM version, its functions, and available types (OTP and EPROM).

5.1.1 Outline

Outlines the capabilities of the built-in PROM version, including programming methods and suitability for different production volumes.

5.2 EPROM version

Describes the EPROM version, its operating modes (Normal, EPROM), and related pins.

5.2.1 EPROM mode pins

Lists pin functions specifically for the EPROM mode, detailing their roles in programming and verification.

5.2.2 Input/Output signals

Explains the input/output signals for Read, Program, and Erase operations in EPROM mode.

5.2.3 Algorithm Programming

Details the step-by-step algorithm for programming the built-in PROM, including voltage settings and pulse application.

5.3 Usage Precaution

Provides precautions for using built-in PROM versions, including handling of high voltage and protection of the EPROM window.

5.3.1 Built-in PROM versions

Offers specific cautions for programming built-in PROM versions, emphasizing voltage and power-on sequences.

5.3.2 One-time PROM versions

Highlights that OTP versions are not tested/screened, recommending programming and testing for reliability.

5.3.3 EPROM versions

Advises on protecting the EPROM window from light and cleaning it before erasure for optimal performance.

Chapter 6 Standard Characteristics

6.1 Standard DC Characteristics

Presents standard DC characteristics of the M30240EC, including output currents and voltage ratings.