Overview - Renesas M16C Series User Manual

M30240 Group

1.1.7 Overview

The M30240 group is a single chip PC peripheral microcontroller based on the Universal Serial Bus
(USB) Version 1.1 specification. This device provides interface between a USB-equipped host computer
and PC peripherals such as telephones, audio systems, and digital cameras. The M30240 block
diagram is shown in Figure 1.4.
The USB function control unit of the M30240 group can support all four data transfer types listed in the
USB specification: Isochronous, Interrupt, Bulk, and Control. Each transfer type is used for controlling a
different set of PC peripherals. Isochronous transfers provide guaranteed bus access, a constant data
rate, and error tolerance for devices such as computer-telephone integration (CTI) and audio systems.
Interrupt transfers are designed to support human input devices (HID) that communicate small amounts
of data infrequently. Bulk transfers are necessary for devices such as digital cameras and scanners that
communicate large amounts of data to the PC as bus bandwidth becomes free. Finally, control transfers
are supported and are useful for bursty, host-initiated type communication where bus management is
the primary concern.
Figure 1.4: M30240 block diagram
Rev.1.00 Sep 24, 2003 Page 9 of 360
UART x 3
LED Drivers
Timers x 8
(X 8)
Watchdog
Timer
A-D
Converter
CRC Circuit
(Normal MCU or DMA Transfer)
I/O Ports (P0~P3, P6 ~ P8, P10)
1 - 12MHz
frequency
48 MHz
synthesizer
RAM
ROM
M16C CPU
DMAC x 2
FIFOs
Overview
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