368
Chapter 13
Serial Interface Function
Preliminary User’s Manual U15839EE1V0UM00
Figure 13-2:
Asynchronous Serial Interface Mode Registers (ASIM0, ASIM1) (2/3)
Remark:
When reception is disabled, the reception shift register does not detect a start bit. No shift-in
processing or transfer processing to the reception buffer register (RXBn) is performed, and
the contents of the RXBn register are retained.
When reception is enabled, the reception shift operation starts, synchronized with the
detection of the start bit, and when the reception of one frame is completed, the contents of
the reception shift register are transferred to the RXBn register. A reception completion
interrupt (INTSRn) is also generated in synchronization with the transfer to the RXBn
register.
Bit Position
Bit Name
Function
5
RXE
Enables/disables reception.
0: Disable reception (Perform synchronous reset of reception circuit)
1: Enable reception
Cautions: 1. Set the RXE bit to 1 after setting the Power bit to 1 when
starting transfer. Set the Power bit to 0 after setting the RXE
bit to 0 when stopping transfer.
2. To initialize the reception unit status, clear (0) the RXE bit, and
after letting 2 Clock cycles (base clock) elapse, set (1) the RXE
bit again. If the RXE bit is not set again,
initialization may not be successful. (For details about the
base clock, refer to 13.2.6 “Dedicated baud rate generators
(BRG) of UART5n (n = 0, 1)” on page 384
4, 3
PS1, PS0
Controls parity bit.
PS1
PS0
Transmit Operation
Receive Operation
0
0
Don’t output parity bit
Receive with no parity
0
1
Output 0 parity
Receive as 0 parity
1
0
Output odd parity
Judge as odd parity
1
1
Output even parity
Judge as even parity
Cautions: 1. To overwrite the PS1 and PS0 bits, first clear (0) the TXE and
RXE bits.
2. If "0 parity" is selected for reception, no parity judgment is
performed. Therefore, no error interrupt is generated because
the PE bit of the ASISn register is not set.
• Even parity
If the transmit data contains an odd number of bits with the value “1”, the parity bit
is set (1). If it contains an even number of bits with the value “1”, the parity bit is
cleared (0). This controls the number of bits with the value “1” contained in the
transmit data and the parity bit so that it is an even number.
During reception, the number of bits with the value “1” contained in the receive
data and the parity bit is counted, and if the number is odd, a parity error is
generated.
• Odd parity
In contrast to even parity, odd parity controls the number of bits with the value “1”
contained in the transmit data and the parity bit so that it is an odd number. During
reception, the number of bits with the value “1” contained in the receive data and
the parity bit is counted, and if the number is even, a parity error is generated.
Summary of Contents for mPD703128
Page 6: ...6 Preliminary User s Manual U15839EE1V0UM00 ...
Page 20: ...20 Preliminary User s Manual U15839EE1V0UM00 ...
Page 32: ...32 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 154: ...154 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 238: ...238 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 356: ...356 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 522: ...522 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 600: ...600 Preliminary User s Manual U15839EE1V0UM00 MEMO ...
Page 610: ...610 Preliminary User s Manual U15839EE1V0UM00 ...
Page 612: ......