Datasheet

ADuC7033
Rev. B | Page 111 of 140
UART Control Register 1
Name: COMCON1
Address: 0xFFFF0710
Default Value: 0x00
Access: Read/write
Function: This 8-bit register controls the operation of the UART in conjunction with COMCON0.
Table 82. COMCON1 MMR Bit Designations
Bit Name Description
7 to 6 UART Input Mux.
00 = RxD driven by LIN input; required for LIN communications using the LIN pin.
01 = reserved.
10 = RxD driven by GP5; required for serial communications using GPIO_5 pin (RxD).
11 = reserved.
5 Reserved. Not used.
4 LOOPBACK Loopback. Set by user to enable loopback mode. In loopback mode, the TxD is forced high.
3 to 0 Reserved. Not used.
UART Status Register 0
Name: COMSTA0
Address: 0xFFFF0714
Default Value: 0x60
Access: Read only
Function: This 8-bit, read-only register reflects the current status on the UART.
Table 83. COMSTA0 MMR Bit Designations
Bit Name Description
7 Reserved.
6 TEMT COMTX and Shift Register Empty Status Bit.
Set automatically if COMTX and the shift register are empty. This bit indicates that the data has been
transmitted, that is, it is no longer present in the shift register.
Cleared automatically when writing to COMTX.
5 THRE COMTX Empty Status Bit.
Set automatically if COMTX is empty. COMTX can be written as soon as this bit is set, the previous data
may not have been transmitted yet and can still be present in the shift register.
Cleared automatically when writing to COMTX.
4 BI Break Indicator.
Set when SIN is held low for more than the maximum word length.
Cleared automatically.
3 FE Framing Error.
Set when the stop bit is invalid.
Cleared automatically.
2 PE Parity Error.
Set when a parity error occurs.
Cleared automatically.
1 OE Overrun Error.
Set automatically if data are overwritten before being read.
Cleared automatically.
0 DR Data Ready.
Set automatically when COMRX is full.
Cleared by reading COMRX.