UPD78F0138 NEC, UPD78F0138 Datasheet - Page 278

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

(2) Asynchronous serial interface reception error status register 0 (ASIS0)
278
Address: FF73H After reset: 00H R
Cautions 1. The operation of the PE0 bit differs depending on the set values of the PS01 and PS00 bits of
Symbol
ASIS0
This register indicates an error status on completion of reception by serial interface UART0. It includes three
error flag bits (PE0, FE0, OVE0).
This register is read-only by an 8-bit memory manipulation instruction.
RESET input clears this register to 00H if bit 7 (POWER0) and bit 5 (RXE0) of ASIM0 = 0. 00H is read when this
register is read.
Figure 13-3. Format of Asynchronous Serial Interface Reception Error Status Register 0 (ASIS0)
2. Only the first bit of the receive data is checked as the stop bit, regardless of the number of
3. If an overrun error occurs, the next receive data is not written to receive buffer register 0
4. If data is read from ASIS0, a wait cycle is generated. Do not read data from ASIS0 when the
OVE0
PE0
FE0
asynchronous serial interface operation mode register 0 (ASIM0).
stop bits.
(RXB0) but discarded.
CPU is operating on the subsystem clock and the X1 input clock is stopped. For details, see
CHAPTER 34 CAUTIONS FOR WAIT.
7
0
0
1
0
1
0
1
If POWER0 = 0 and RXE0 = 0, or if ASIS0 register is read.
If the parity of transmit data does not match the parity bit on completion of reception.
If POWER0 = 0 and RXE0 = 0, or if ASIS0 register is read.
If the stop bit is not detected on completion of reception.
If POWER0 = 0 and RXE0 = 0, or if ASIS0 register is read.
If receive data is set to the RXB register and the next reception operation is completed before the
data is read.
6
0
CHAPTER 13 SERIAL INTERFACE UART0
5
0
User’s Manual U16228EJ2V0UD
Status flag indicating framing error
Status flag indicating overrun error
Status flag indicating parity error
4
0
3
0
PE0
2
FE0
1
OVE0
0