SST89E554 SST [Silicon Storage Technology, Inc], SST89E554 Datasheet - Page 23

• Manufacturer Part Number: SST89E554
• Description: FlashFlex51 MCU
• Manufacturer: SST [Silicon Storage Technology, Inc]

FlashFlex51 MCU
SST89E564 / SST89V564 / SST89E554 / SST89V554
Preliminary Specifications
Serial Port Control Register (SCON)
©2001 Silicon Storage Technology, Inc.
Location
98H
Symbol
FE
SM0
SM1
SM2
REN
TB8
RB8
TI
RI
SM0/FE
7
SM1
Function
Set SMOD0 = 1 to access FE bit.
0: No framing error
1: Framing Error. Set by receiver when an invalid stop bit is detected. This bit needs to
be cleared by software.
SMOD0 = 0 to access SM0 bit.
Serial Port Mode Bit 0
Serial Port Mode Bit 1
Enables the Automatic Address Recognition feature in Modes 2 or 3. If SM2 = 1 then RI
will not be set unless the received 9th data bit (RB8) is 1, indicating an address, and the
received byte is a Given or broadcast Address. In Mode 1, if SM2 = 1 then RI will not be
activated unless a valid stop bit was received, and the received byte is a Given or
Broadcast Address. In Mode 0, SM2 should be 0.
Enables serial reception.
0: to disable reception.
1: to enable reception.
The 9th data bit that will be transmitted in Modes 2 and 3. Set or clear by software as
desired.
In Modes 2 and 3, the 9th data bit that was received. In Mode 1, if SM2 - 0, RB8 is the
stop bit that was received. In Mode 0, RB8 is not used.
Transmit interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or at the
beginning of the stop bit in the other modes, in any serial transmission, Must be cleared
by software.
Receive interrupt flag. Set by hardware at the end of the8th bit time in Mode 0, or halfway
through the stop bit time in the other modes, in any serial reception (except see SM2).
Must be cleared by software.
6
1. f
SM0
OSC
0
0
1
1
= oscillator frequency
SM2
5
SM1
0
1
0
1
REN
4
23
Mode
TB8
3
0
1
2
3
Description
Shift Register
8-bit UART
9-bit UART
9-bit UART
RB8
2
TI
1
Baud Rate
f
12 (12 clock mode)
Variable
f
mode) or f
f
Variable
OSC
OSC
OSC
/6 (6 clock mode) or f
/32 or f
/32 (12 clock mode)
RI
0
OSC
1
OSC
S71181-03-000 9/01
/64 or
/16 (6 clock
Reset Value
00000000b
OSC
/
384