ADuCM310 Hardware Reference Manual
UG-549
Rev. C | Page 155 of 192
Line Status Register
Address: 0x40005014, Reset: 0x0060, Name: COMLSR
Table 220. Bit Descriptions for COMLSR
Bits
Bit Name
Description
Reset
Access
[15:7]
RESERVED
Reserved.
0x0
R
6
TEMT
COMTX and shift register empty status.
0x1
R
0: COMTX has been written to and contains data to be transmitted. Take
care not to overwrite its value.
1: COMTX and the transmit shift register are empty, and it is safe to write
new data to COMTX. Data has been transmitted.
5
THRE
COMTX empty. THRE is cleared when COMRX is read.
0x1
R
0: COMTX has been written to and contains data to be transmitted. Take
care taken not to overwrite its value.
1: COMTX is empty, and it is safe to write new data to COMTX. The previous
data may not have been transmitted yet and may still be present in the
shift register.
4
BI
Break indicator. If set, this bit self clears after COMLSR is read.
0x0
RC
0: SIN is not detected to be longer than the maximum word length.
1: SIN is held low for more than the maximum word length.
3
FE
Framing error. If set, this bit self clears after COMLSR is read.
0x0
RC
0: no invalid stop bit is detected.
1: an invalid stop bit is detected on a received word.
2
PE
Parity error. If set, this bit self clears after COMLSR is read.
0x0
RC
0: no parity error is detected.
1: a parity error has occurred on a received word.
1
OE
Overrun error. If set, this bit self clears after COMLSR is read.
0x0
RC
0: receive data has not been overwritten.
1: receive data was overwritten by new data before COMRX was read.
0
DR
Data ready. This bit is cleared only by reading COMRX. It does not self clear. 0x0
RC
0: COMRX does not contain new receive data.
1: COMRX contains receive data to be read.
Modem Status Register
Address: 0x40005018, Reset: 0x0000, Name: COMMSR
Table 221. Bit Descriptions for COMMSR
Bits
Bit Name
Description
Reset
Access
[15:8]
RESERVED
Reserved.
0x0
R
7
DCD
Data carrier detect. This bit reflects the direct status complement of the
DCD pin.
0x0
R
0: DCD is logic high.
1: DCD is logic low.
6
RI
Ring indicator. This bit reflects the direct status complement of the DCD pin.
0x0
R
0: RI is logic high.
1: RI is logic low.
5
DSR
Data set ready. This bit reflects the direct status complement of the DCD pin. 0x0
R
0: DSR is logic high.
1: DSR is logic low.
4
CTS
Clear to send. This bit reflects the direct status complement of the DCD pin.
0x0
R
0: CTS is logic high.
1: CTS is logic low.
3
DDCD
Delta DCD. If set, this bit self clears after COMMSR is read.
0x0
R
0: DCD has not changed state since COMMSR was last read.
1: DCD has changed state since COMMSR last read.