Siemens ERTEC200 - Manual (Page 50)

4.6.2 UART Register Description
UARTDR R/W Addr.: 0x4000_2300 Default: 0x--
Description UART data registers
Bit No. Name Description
7 – 0 ------- WRITE:
-
If FIFO is enabled, the written data are entered in the FIFO.
- If FIFO is disabled, the written data are entered in the Transmit holding register
(the first word in the Transmit FIFO).
READ:
- If FIFO is enabled, the received data are entered in the FIFO.
- If FIFO is disabled, the received data are entered in the Receive holding register
(the first word in the RECEIVE FIFO).
NOTE: When data are received, the UARTDR data register must be read out first and then the UARTRSR error register.
UARTRSR/UARTECR R/W Addr.: 0x4000_2304 Default: 0x00
Description UART receive status register (read)
UART receive error clear register (write)
Bit No. Name Description
7 – 0 ------- (Write) Framing errors, parity errors, break errors, and overrun errors are deleted.
0 FE (Read) Framing error = 1 Received character does not have a valid stop bit
1 PE (Read) Parity error = 1 Parity of received character does not match the assigned parity in
the UARTLCR_H register Bit 2.
2 BE (Read) Break error = 1 A break was detected. A break means that the received data are at
LOW for longer than a standard character with all control bits.
3 OE (Read) Overrun-Error = 1 If the FIFO is full and a new character is received.
7 – 4 ------- (Read) Reserved
Value is undefined
NOTE: When new data are displayed, the UARTDR data register must be read out first and then the UARTRSR error
register. The error register is not updated until the data register is read.
Copyright © Siemens AG 2007. All rights reserved. 50 ERTEC 200 Manual
Technical data subject to change Version 1.1.0