Section 15 Serial Communication Interface with FIFO (SCIF)
Rev. 0.50 May 18, 2006 Page 762 of 1588
REJ09B0313-0050
15.6 Usage
Notes
Note the following when using the SCIF.
15.6.1
SCFTDR Writing and TDFE Flag
The TDFE flag in the serial status register (SCFSR) is set when the number of transmit data bytes
written in the transmit FIFO data register (SCFTDR) has fallen below the transmit trigger number
set by bits TTRG[1:0] in the FIFO control register (SCFCR). After the TDFE flag is set, transmit
data up to the number of empty bytes in SCFTDR can be written, allowing efficient continuous
transmission.
However, if the number of data bytes written in SCFTDR is equal to or less than the transmit
trigger number, the TDFE flag will be set to 1 again after being read as 1 and cleared to 0. TDFE
flag clearing should therefore be carried out when SCFTDR contains more than the transmit
trigger number of transmit data bytes.
The number of transmit data bytes in SCFTDR can be found from the upper 8 bits of the FIFO
data count register (SCFDR).
15.6.2
SCFRDR Reading and RDF Flag
The RDF flag in the serial status register (SCFSR) is set when the number of receive data bytes in
the receive FIFO data register (SCFRDR) has become equal to or greater than the receive trigger
number set by bits RTRG[1:0] in the FIFO control register (SCFCR). After RDF flag is set,
receive data equivalent to the trigger number can be read from SCFRDR, allowing efficient
continuous reception.
However, if the number of data bytes in SCFRDR exceeds the trigger number, the RDF flag will
be set to 1 again if it is cleared to 0. The RDF flag should therefore be cleared to 0 after being read
as 1 after reading the number of the received data in the receive FIFO data register (SCFRDR)
which is less than the trigger number.
The number of receive data bytes in SCFRDR can be found from the lower 8 bits of the FIFO data
count register (SCFDR).
Summary of Contents for Single-Chip Microcomputer SH7203
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Page 52: ...Section 1 Overview Rev 0 50 May 18 2006 Page 22 of 1588 REJ09B0313 0050 ...
Page 98: ...Section 2 CPU Rev 0 50 May 18 2006 Page 68 of 1588 REJ09B0313 0050 ...
Page 128: ...Section 4 Clock Pulse Generator CPG Rev 0 50 May 18 2006 Page 98 of 1588 REJ09B0313 0050 ...
Page 200: ...Section 6 Interrupt Controller INTC Rev 0 50 May 18 2006 Page 170 of 1588 REJ09B0313 0050 ...
Page 242: ...Section 8 Cache Rev 0 50 May 18 2006 Page 212 of 1588 REJ09B0313 0050 ...
Page 400: ...Section 9 Bus State Controller BSC Rev 0 50 May 18 2006 Page 370 of 1588 REJ09B0313 0050 ...
Page 696: ...Section 13 Watchdog Timer WDT Rev 0 50 May 18 2006 Page 666 of 1588 REJ09B0313 0050 ...
Page 726: ...Section 14 Realtime Clock RTC Rev 0 50 May 18 2006 Page 696 of 1588 REJ09B0313 0050 ...
Page 876: ...Section 17 I2 C Bus Interface 3 IIC3 Rev 0 50 May 18 2006 Page 846 of 1588 REJ09B0313 0050 ...
Page 1054: ...Section 21 D A Converter DAC Rev 0 50 May 18 2006 Page 1024 of 1588 REJ09B0313 0050 ...
Page 1294: ...Section 24 LCD Controller LCDC Rev 0 50 May 18 2006 Page 1264 of 1588 REJ09B0313 0050 ...
Page 1386: ...Section 26 I O Ports Rev 0 50 May 18 2006 Page 1356 of 1588 REJ09B0313 0050 ...
Page 1512: ...Section 30 List of Registers Rev 0 50 May 18 2006 Page 1482 of 1588 REJ09B0313 0050 ...
Page 1598: ...Section 31 Electrical Characteristics Rev 0 50 May 18 2006 Page 1568 of 1588 REJ09B0313 0050 ...
Page 1606: ...Appendix Rev 0 50 May 18 2006 Page 1576 of 1588 REJ09B0313 0050 ...
Page 1618: ...Rev 0 50 May 18 2006 Page 1588 of 1588 REJ09B0313 0050 ...
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Page 1622: ...SH7203 Group Hardware Manual ...