h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 666

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 18 Universal Serial Bus Interface (USB)
18.4.4
Figures 18.10 to 18.13 show the USB function core and LSI firmware operations when the USB
function core receives an IN token (IN transaction). An IN transaction is used for data stage and
status stage of control transfer, interrupt transfer, and bulk transfer.
Rev. 3.00 Jan 25, 2006 page 614 of 872
REJ09B0286-0300
Note: * When an EP2TS interrupt is specified as a USBIB or USBIC interrupt according to the INTSELR0 setting, the corresponding
Receive an IN data
Send an IN token
Figure 18.10 Operation on Receiving an IN Token (EP2-IN: Initial FIFO Is Full)
handshake packet
packet (8 bytes)
Send an ACK
interrupt occurs. In this case, if a USBIB or USBIC interrupt occurs, interrupt source determination process is not required.
(Note that TSFR0 must be accessed to clear the flags.)
When a NAK handshake is received from the host, FVSR2 must be rewound to generate an EP2TF interrupt. This EP2TF
interrupt must be handled in the same way as when an IN token is received while the FIFO is empty since an EP2TF interrupt
caused by a NAK handshake and that caused by an IN token are difficult to be distinguished.
USB Host
packet
Operation on Receiving an IN Token (Endpoints 0, 1, 2, 3 and 4)
USB Function Core
Send an IN data
packet (8 bytes)
the slave CPU
Receive an IN
Send ACK to
Receive ACK
token packet
enable data transmission
Write data to the EP2
Read data from EP2
Request an USBID
Modify FVSR2 and
interrupt (EP2TS) *
Core Interface
Modify FVSR2
FIFO
FIFO
if an EP2TS interrupt occurs
Read FVSR2 and write data
Read USBIFR0 and check
to EPDR2 for the number
Clear the EP2TS bit of
Read TSFR0 and check
if a TS interrupt occurs
written to the EP2 FIFO
Complete the USBID
of bytes which can be
interrupt processing
Set the EP2TE bit of
interrupt processing
Initiate the USBID
PTTER0 to 1
TSFR0 to 0
Slave CPU
or not
or not