Section 16 Serial Communication Interface (SCI, IrDA, and CRC)
Rev. 3.00 Jan 25, 2006 page 392 of 872
REJ09B0286-0300
•
Serial interface control register (SCICR)*
1
•
Serial enhanced mode register (SEMR)*
2
•
Serial RFU enable register (SCIDTER)*
2
Notes: 1. SCICR is not available in SCI_0 or SCI_2.
2. SEMR and SCIDTER are not available in SCI_1.
16.3.1
Receive Shift Register (RSR)
RSR is a shift register used to receive serial data that converts it into parallel data. When one
frame of data has been received, it is transferred to RDR automatically. RSR cannot be directly
accessed by the CPU.
16.3.2
Receive Data Register (RDR)
RDR is an 8-bit register that stores receive data. When the SCI has received one frame of serial
data, it transfers the received serial data from RSR to RDR where it is stored. After this, RSR can
receive the next data. Since RSR and RDR function as a double buffer in this way, continuous
receive operations be performed. After confirming that the RDRF bit in SSR is set to 1, read RDR
for only once. RDR cannot be written to by the CPU.
16.3.3
Transmit Data Register (TDR)
TDR is an 8-bit register that stores transmit data. When the SCI detects that TSR is empty, it
transfers the transmit data written in TDR to TSR and starts transmission. The double-buffered
structures of TDR and TSR enables continuous serial transmission. If the next transmit data has
already been written to TDR when one frame of data is transmitted, the SCI transfers the written
data to TSR to continue transmission. Although TDR can be read from or written to by the CPU at
all times, to achieve reliable serial transmission, write transmit data to TDR for only once after
confirming that the TDRE bit in SSR is set to 1.
16.3.4
Transmit Shift Register (TSR)
TSR is a shift register that transmits serial data. To perform serial data transmission, the SCI first
transfers transmit data from TDR to TSR, then sends the data to the TxD pin. TSR cannot be
directly accessed by the CPU.
Summary of Contents for H8S/2158
Page 10: ...Rev 3 00 Jan 25 2006 page viii of lii...
Page 36: ...Rev 3 00 Jan 25 2006 page xxxiv of lii B Product Lineup 863 C Package Dimensions 864 Index 865...
Page 47: ...Rev 3 00 Jan 25 2006 page xlv of lii Appendix Figure C 1 Package Dimensions TBP 112A 864...
Page 54: ...Rev 3 00 Jan 25 2006 page lii of lii...
Page 70: ...Section 1 Overview Rev 3 00 Jan 25 2006 page 16 of 872 REJ09B0286 0300...
Page 118: ...Section 3 MCU Operating Modes Rev 3 00 Jan 25 2006 page 64 of 872 REJ09B0286 0300...
Page 126: ...Section 4 Exception Handling Rev 3 00 Jan 25 2006 page 72 of 872 REJ09B0286 0300...
Page 198: ...Section 6 Bus Controller Rev 3 00 Jan 25 2006 page 144 of 872 REJ09B0286 0300...
Page 326: ...Section 10 8 Bit PWM Timer PWM Rev 3 00 Jan 25 2006 page 272 of 872 REJ09B0286 0300...
Page 440: ...Section 15 Watchdog Timer WDT Rev 3 00 Jan 25 2006 page 386 of 872 REJ09B0286 0300...
Page 606: ...Section 17 I 2 C Bus Interface IIC Rev 3 00 Jan 25 2006 page 552 of 872 REJ09B0286 0300...
Page 742: ...Section 19 Multimedia Card Interface MCIF Rev 3 00 Jan 25 2006 page 688 of 872 REJ09B0286 0300...
Page 750: ...Section 21 D A Converter Rev 3 00 Jan 25 2006 page 696 of 872 REJ09B0286 0300...
Page 768: ...Section 22 A D Converter Rev 3 00 Jan 25 2006 page 714 of 872 REJ09B0286 0300...
Page 770: ...Section 23 RAM Rev 3 00 Jan 25 2006 page 716 of 872 REJ09B0286 0300...
Page 824: ...Section 26 Clock Pulse Generator Rev 3 00 Jan 25 2006 page 770 of 872 REJ09B0286 0300...
Page 844: ...Section 27 Power Down Modes Rev 3 00 Jan 25 2006 page 790 of 872 REJ09B0286 0300...
Page 878: ...Section 28 List of Registers Rev 3 00 Jan 25 2006 page 824 of 872 REJ09B0286 0300...
Page 926: ...Index Rev 3 00 Jan 25 2006 page 872 of 872 REJ09B0286 0300...