
19 UART 1
180
EPSON
S1C38000 TECHNICAL MANUAL
bit 7
Divisor Latch Access Bit
0
Receive Buffer/Transmit Holding register and Interrupt Enable register can be
accessed at address 00h and 04h respectively.
1
The divisor latch can be accessed through the Divisor Latch LSB and MSB
registers at address 00h and 04h respectively.
bit 6
Break Control
Setting this bit to 1 causes UART1 to send a break signal by holding the serial output
line low until the Break control bit is reset to 0.
bit 5
Mark or Space Parity
0
Mark or Space parity is disabled
1
When the Enable Parity bit is 1 and the Even Parity bit is 1, the parity bit is
transmitted and checked as a logic 0. When the Enable Parity bit is 1 and the
Even Parity bit is 0, the parity bit is transmitted and checked as a logic 1.
bit 4
Even Parity
0
Set odd parity
1
Set even parity
bit 3
Parity Enable
0
Disable parity
1
Enable parity
bit 2
Number of Stop Bits
This bit selects the number of stop bits transmitted. The receiver checks the first stop bit
only, regardless of the number of stop bits selected.
01 stop bit
1
When 6, 7, or 8 bits per character is selected, 2 stop bits are generated. When 5 bits
per character is selected, one and a half stop bit is generated.
bits 1–0
Word Length Bits [1:0]
These bits select the number of bits-per-character transmitted and received.
00
5 bits
01
6 bits
10
7 bits
11
8 bits
bit 4
Loop Back
When this bit is set, data on the serial out line is looped backed to the serial in line. In
this mode all interrupts are functional. This feature is used for diagnostic purposes.
bit 1
RTS Control
This bit controls directly the RTS1 output. When this bit is 0 the RTS1 output is 1. When
this bit is 1 the RTS1 output is 0.
Line Control Register
URT1[0Ch]
Default = 0000 0000h
Read/Write
n/a
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
n/a
DLAB
Break
Control
Mark or
Space
Parity
Even
Parity
Enable
Number
of Stop
Bits
Word Length
15
14
13
12
11
10
9876543210
Modem Control Register
URT1[10h]
Default = 0000 0000h
Read/Write
n/a
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
n/a
Loop
Back
n/a
RTS
Control
n/a
15
14
13
12
11
10
9876543210