Renesas SH7781 - page 1174

22. Serial I/O with FIFO (SIOF)
Rev.1.00 Jan. 10, 2008 Page 1144 of 1658
REJ09B0261-0100
22.4.8 Interrupts
The SIOF has one type of interrupt.
(1) Interrupt Sources
Interrupts can be issued by several sources. Each source is shown as an SIOF status in SISTR.
Table 22.14 lists the SIOF interrupt sources.
Table 22.14 SIOF Interrupt Sources
No. Classification Bit Name Function Name Description
1 TDREQ Transmit FIFO transfer
request
The transmit FIFO stores data of
specified size or more.
2
Transmission
TFEMP Transmit FIFO empty The transmit FIFO is empty.
3 RDREQ Receive FIFO transfer
request
The receive FIFO stores data of
specified size or more.
4
Reception
RFFUL Receive FIFO full The receive FIFO is full.
5 TCRDY Transmit control data
ready
The transmit control register is ready to
be written to.
6
Control
RCRDY Receive control data
ready
The receive control data register stores
valid data.
7 Error TFUDF Transmit FIFO
underflow
Serial data transmit timing has arrived
while the transmit FIFO is empty.
8 TFOVF Transmit FIFO overflow Write to the transmit FIFO is performed
while the transmit FIFO is full.
9 RFOVF Receive FIFO overflow Serial data is received while the receive
FIFO is full.
10 RFUDF Receive FIFO
underflow
The receive FIFO is read while the
receive FIFO is empty.
11 FSERR Frame Synchronous
Error
A synchronous signal is input before
the specified bit number has been
passed (in slave mode).
12 SAERR Slot assign error The same slot is specified in both serial
data and control data.
Whether an interrupt is issued or not as the result of an interrupt source is determined by the
SIIER settings. If an interrupt source is set to 1 and the corresponding bit in SIIER is set to 1, an
SIOF interrupt is issued.