P89C668 Philips Semiconductors, P89C668 Datasheet - Page 18

• Manufacturer Part Number: P89C668
• Description: 80C51 8-bit Flash microcontroller family 64KB ISP FLASH with 8KB RAM
• Manufacturer: Philips Semiconductors

Philips Semiconductors
2001 Jul 27
80C51 8-bit Flash microcontroller family
64KB ISP Flash with 8KB RAM
Figure 9. UART Multiprocessor Communication, Automatic Address Recognition
START
BIT
IN UART MODE 2 OR MODE 3 AND SM2 = 1:
– WHEN OWN ADDRESS RECEIVED, CLEAR SM2 TO RECEIVE DATA BYTES
– WHEN ALL DATA BYTES HAVE BEEN RECEIVED: SET SM2 TO WAIT FOR NEXT ADDRESS.
D0
SM0 / FE
INTERRUPT IF REN=1, RB8=1 AND “RECEIVED ADDRESS” = “PROGRAMMED ADDRESS”
RECEIVED ADDRESS D0 TO D7
SMOD1
PROGRAMMED ADDRESS
D0
0 : S0CON.7 = SM0
1 : S0CON.7 = FE
D1
SMOD0
SM1
D1
Figure 8. UART Framing Error Detection
D2
SM2
SM0
D2
–
1
1
D3
REN
SM1
D3
POF
DATA BYTE
1
0
SET FE BIT IF STOP BIT IS 0 (FRAMING ERROR)
SM0 TO UART MODE CONTROL
D4
18
TB8
D4
SM2
LVF
COMPARATOR
D5
1
D5
RB8
GF0
REN
1
D6
D6
GF1
TB8
TI
D7
X
D7
RB8
IDL
D8
RI
MODE 2, 3
ONLY IN
D8
S0CON
(98H)
PCON
(87H)
TI
STOP
BIT
SU01458
RI
P89C668
Preliminary data
S0CON
SU01459
(98H)