W83977A Winbond Electronics Corp America, W83977A Datasheet - Page 50

• Manufacturer Part Number: W83977A
• Description: Winbond I/O
• Manufacturer: Winbond Electronics Corp America

Bit 4: EPE. This bit describes the number of logic 1's in the data word bits and parity bit only when bit 3 is
Bit 3: PBE. When this bit is set, the position between the last data bit and the stop bit of the SOUT will be
Bit 2: MSBE. This bit defines the number of stop bits in each serial character that is transmitted or
Bits 0 and 1: DLS0, DLS1. These two bits define the number of data bits that are sent or checked in
TABLE 3-2 WORD LENGTH DEFINITION
3.2.2 UART Status Register (USR) (Read/Write)
This 8-bit register provides information about the status of the data transfer during communication.
Bit 7: RFEI. In 16450 mode, this bit is always set to a logic 0. In 16550 mode, this bit is set to a logic 1
DLS1
programmed. When this bit is set, an even number of logic 1's are sent or checked. When the bit
is reset, an odd number of logic 1's are sent or checked.
stuffed with the parity bit at the transmitter. For the receiver, the parity bit in the same position as
the transmitter will be detected.
received.
(1) If MSBE is set to a logical 0, one stop bit is sent and checked.
(2) If MSBE is set to a logical 1, and data length is 5 bits, one and a half stop bits are sent and
(3) If MSBE is set to a logical 1, and data length is 6, 7, or 8 bits, two stop bits are sent and
when there is at least one parity bit error, no stop bit error or silent byte detected in the FIFO. In
16550 mode, this bit is cleared by reading from the USR if there are no remaining errors left in
the FIFO.
0
0
1
1
checked.
checked.
each serial character.
DLS0
7
0
1
0
1
6
5
4
DATA LENGTH
3
5 bits
6 bits
7 bits
8 bits
2
1
0
- 42 -
Overrun error (OER)
Parity bit error (PBER)
No stop bit error (NSER)
Silent byte detected (SBD)
Transmitter Buffer Register empty (TBRE)
Transmitter Shift Register empty (TSRE)
RBR Data ready (RDR)
RX FIFO Error Indication (RFEI)
Publication Release Date: March 1998
W83977TF
PRELIMINARY
Revision 0.62