m5m51016btp Renesas Electronics Corporation., m5m51016btp Datasheet - Page 136

• Manufacturer Part Number: m5m51016btp
• Description: Renesas 16-bit Single-chip Microcomputer M16c Family / M16c/20 Series
• Manufacturer: Renesas Electronics Corporation.

M30245 Group
Rev.2.00 Oct 16, 2006
REJ09B0340-0200
2.8 USB function
2.8.1 Overview
The USB function control unit of the M30245 group is compliant with USB2.0 specification and supports
Full-Speed transfer. USB2.0 specification defines the following four kinds of transfer types:
The USB function control unit is provided with 9 endpoints including endpoint 0, endpoints 1 to 4 OUT
(receive) and endpoints 1 to 4 IN (transmit), each of which having an FIFO. The endpoint 0 can apply only
to the control transfer (same in transfer form as the bulk transfer); while endpoints 1 to 4 IN/OUT can
apply to the bulk transfer, isochronous transfer and interrupt transfer. The size and the starting position of
endpoints 1 to 4 IN/OUT FIFO can be set according to the user's system (The size and the starting
position of endpoint 0 IN/OUT FIFO are fixed). Further, when the double buffer mode is enabled, the
buffer which has twice as much as the set size is available for the IN/OUT FIFO. When the continuous
receive/transmit mode is enabled, data can be transferred at a high speed (in bulk transfer).
The USB related interrupts include USB suspend interrupt, USB resume interrupt, USB reset interrupt,
USB endpoint 0 interrupt, USB function interrupt, and USB SOF interrupt. The USB function control unit
can control the state transition of the USB device based on these interrupt requests.
(1) Transfer Type
Control Transfer
Isochronous Transfer
Interrupt Transfer
Bulk Transfer
The USB specifications largely concern 2 types, including the one for the host side (PC/Hub) to control
the connected peripheral devices and the other for the peripheral device side (Device) which is con-
nected to the real machine. Further, depending on the number of data dealt with in the device, the
peripheral devices which require more data (concerning image, audio, etc.) at one time have the
communication specification with high transfer speed (12Mbps) called Full-Speed function, while the
peripheral devices (keyboard, mouse) which require less data have the communication specification
with low transfer speed (1.5Mbps) called Low-Speed function. Further, a communication specification
with even higher speed is available which is called Hi-Speed function (480Mbps).
These communication specifications are each determined by device class of the peripheral devices
and the transfer type to be used is determined for each peripheral device.
The M30245 group supports the following four kinds of transfer types:
This transfer is used for communication of request-response form (bi-directional) in aperiodic com-
munication which occurs suddenly. This is mainly used at the time of setup. As all the devices have
to be supported in the standard device request, control transfer is supported without any exception
for the devices compliant with USB.
This transfer is used to transfer the data which delay does not cause any problem in aperiodic com-
munication which occurs suddenly. This is used to transfer large quantities of data.
Hardware detects errors in order to guarantee transfer data. A request for retransmission is issued
by detecting of any error. For example, they include the output data from printer and image data of
scanner.
Control Transfer
Bulk Transfer
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2. USB function