HD6475328-CP10 Datasheet, PDF (405/459 Pages) Hitachi Semiconductor – original Hitachi CMOS microcomputer unit (MCU)

SSR—Serial Status Register
H'FFDC
SCI
Bit
7
6
5
4
3
2
1
0
TDRE RDRF ORER FER PER
—
—
—
Initial value
1
0
0
0
0
1
1
1
Read/Write R/(W)* R/(W)* R/(W)* R/(W)* R/(W)* —
—
—
Parity Error
0 Cleared from 1 to 0 when:
1. CPU reads PER = 1, then writes 0 in PER.
2. The chip is reset or enters a standby mode.
1 Set to 1 when a parity error occurs (parity of
receive data does not match parity selected by bit).
Framing Error
0 Cleared from 1 to 0 when:
1. CPU reads FER = 1, then writes 0 in FER.
2. The chip is reset or enters a standby mode.
1 Set to 1 when a framing error occurs (stop bit is 0).
Overrun Error
0 Cleared from 1 to 0 when:
1. CPU reads ORER = 1, then writes 0 in ORER.
2. The chip is reset or enters a standby mode.
1 Set to 1 when an overrun error occurs (next data is
completely received while RDRF bit is set to 1).
Receive Data Register Full
0 Cleared from 1 to 0 when:
1. CPU reads RDRF = 1, then writes 0 in RDRF.
2. RDR is read by the DTC.
3. The chip is reset or enters a standby mode.
1 Set to 1 when one character is received normally and
transferred from RSR to RDR.
Transmit Data Register Empty
0 Cleared from 1 to 0 when:
1. CPU reads TDRE = 1, then writes 0 in TDRE.
2. The DTC writes data in TDR.
1 Set to 1 when:
1. The chip is reset or enters a standby mode.
2. Data is transferred from TDR to TSR.
3. CPU reads TDRE = 0, then clears 0 in TE.
* Only writing of 0 to clear the flag is enabled.
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