Section 10 Serial Communication Interface
Rev. 6.00 Aug 04, 2006 page 351 of 680
REJ09B0145-0600
10.3.2
Register Descriptions
1. Receive Shift Register (RSR)
Bit
Read/Write
7
6
5
4
3
0
2
1
RSR is a register used to receive serial data. Serial data input to RSR from the RXD
3X
pin is set in
the order in which it is received, starting from the LSB (bit 0), and converted to parallel data.
When one byte of data is received, it is transferred to RDR automatically.
RSR cannot be read or written directly by the CPU.
2. Receive Data Register (RDR)
Bit
Initial value
Read/Write
7
RDR7
0
R
6
RDR6
0
R
5
RDR5
0
R
4
RDR4
0
R
3
RDR3
0
R
0
RDR0
0
R
2
RDR2
0
R
1
RDR1
0
R
RDR is an 8-bit register that stores received serial data.
When reception of one byte of data is finished, the received data is transferred from RSR to RDR,
and the receive operation is completed. RSR is then able to receive data. RSR and RDR are
double-buffered, allowing consecutive receive operations.
RDR is a read-only register, and cannot be written by the CPU.
RDR is initialized to H'00 upon reset, and in standby, watch or module standby mode.
Summary of Contents for H8/38342
Page 8: ...Rev 6 00 Aug 04 2006 page vi of xxxvi...
Page 12: ...Rev 6 00 Aug 04 2006 page x of xxxvi...
Page 38: ...Rev 6 00 Aug 04 2006 page xxxvi of xxxvi...
Page 76: ...Section 1 Overview Rev 6 00 Aug 04 2006 page 38 of 680 REJ09B0145 0600...
Page 240: ...Section 7 RAM Rev 6 00 Aug 04 2006 page 202 of 680 REJ09B0145 0600...
Page 468: ...Section 12 A D Converter Rev 6 00 Aug 04 2006 page 430 of 680 REJ09B0145 0600...
Page 580: ...Section 15 Electrical Characteristics Rev 6 00 Aug 04 2006 page 542 of 680 REJ09B0145 0600...