peb20560 Infineon Technologies Corporation, peb20560 Datasheet - Page 189

• Manufacturer Part Number: peb20560
• Description: Dsp Oriented Pbx Controller Doc
• Manufacturer: Infineon Technologies Corporation

2.14.1.1
LCR
The system programmer specifies the format of the asynchronous data communications
exchange and sets the divisor latch access bit via the line control register (LCR). The
programmer can also read the contents of the line control register. The read capability
simplifies system programming and eliminates the need for separate storage of the line
characteristics in system memory.
WLS0, WLS1
STB
PEN
EPS
Semiconductor Group
bit
Line Control Register (LCR)
7
DLAB
Bit 1
0
0
1
1
These two bits specify the number of bits in each transmitted or
received serial character. The encoding of bits 0 and 1 is as follows:
This bit specifies the number of stop bits transmitted and received in
each serial character. If bit 2 is a logic 0, one stop bit is generated or
checked in the transmitted data. If bit 2 is a logic 1 when a 5-bit word
length is selected via bits 0 and 1, one and a half stop bits are
generated. If bit 2 is a logic 1 when either a 6-, 7-, or 8-bit word length
is selected, two stop bits are generated. The receiver checks the first
stop-bit only, regardless of the number of stop bits selected.
This bit is the parity enable bit. When bit 3 is a logic 1, a parity bit is
generated (transmit data) or checked (receive data) between the last
data word bit and stop bit of the serial data. (The parity bit is used to
produce an even or odd number of 1’s when the data word bits and
the parity bit are summed).
This bit is the even parity select bit. When bit 3 is a logic 1 and bit 4
is a logic 0, an odd number of logic 1’s is transmitted or checked in
the data word bits and parity bit. When bit 3 is a logic 1 and bit 4 is a
logic 1, an even number of logic 1’s is transmitted or checked.
6
SBR
5
STP
Bit 0
0
1
0
1
4
2-143
EPS
3
PEN
Functional Block Description
Character Length
5 Bits
6 Bits
7 Bits
8 Bits
2
STB
1
PEB 20560
WLS
0
2003-08