Modem Control Register; Line Status Register - Analog Devices ADuCM355 Hardware Reference Manual

UG-1262

MODEM CONTROL REGISTER

Address: 0x40005010, Reset: 0x0000, Name: COMMCR
Table 326. Bit Descriptions for COMMCR
Bits Bit Name Settings
[15:5] Reserved
4 LOOPBACK
3 OUT2
2 OUT1
1 RTS
0 DTR

LINE STATUS REGISTER

Address: 0x40005014, Reset: 0x0060, Name: COMLSR
Table 327. Bit Descriptions for COMLSR
Bits Bit Name Settings
[15:6] Reserved
7 FIFOERR
6 TEMT
5 THRE
4 BI
3 FE
2 PE
Description
Reserved.
Loopback Mode. In loopback mode, the UART_SOUT is forced high. The modem signals are
also directly connected to the status inputs (RTS in COMMCR to CTS in COMMSR, DTR in
COMMCR to DSR in COMMSR, OUT1 in COMMCR to RI in COMMSR, and OUT2 in COMMCR
to DCD in COMMSR).
0 Normal operation, loopback disabled.
1 Loop back enabled.
Output 2.
0 Force OUT2 to a Logic 1.
1 Force OUT2 to a Logic 0.
Output 1.
0 Force OUT1 to a Logic 1.
1 Force OUT1 to a Logic 0.
Request to Send.
0 Force RTS to a Logic 1.
1 Force RTS to a Logic 0.
Data Terminal Ready.
0 Force DTR to a Logic 1.
1 Force DTR to a Logic 0.
Description
Reserved.
Data Byte(s) in Receive FIFO have Parity Error, Frame Error, or Break Indication. Only used in
16550 UART mode. This bit is cleared if there are no more errors in the receive FIFO.
COMTX and Shift Register Empty Status.
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.
COMTX Empty. This bit is cleared when COMRX is read.
COMTX has been written to and contains data to be transmitted. Take care not to
0
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 can still be present in the shift register.
Break Indicator. If set, this bit self clears after COMLSR is read.
0 UART_SIN was not detected to be longer than the maximum word length.
1 UART_SIN was held low for more than the maximum word length.
Framing Error. If set, this bit self clears after COMLSR is read.
0 No invalid stop bit was detected.
1 An invalid stop bit was detected on a received word.
Parity Error. If set, this bit self clears after COMLSR is read.
0 No parity error was detected.
1 A parity error occurred on a received word.
ADuCM355
Rev. B | Page 262 of 312
Hardware Reference Manual
Reset Access
0x0 R
0x0 R/W
0x0 R/W
0x0 R/W
0x0 R/W
0x0 R/W
Reset Access
0x0 R
0x0 RC
0x1 R
0x1 R
0x0 RC
0x0 RC
0x0 RC