Philips SC28L91 - Manual (Page 7)

Philips Semiconductors Product data sheet
SC28L91
3.3 V or 5.0 V Universal Asynchronous
Receiver/Transmitter (UART)
2004 Oct 21 7
8
D0–D7
R/WN
CEN
A0–A3
RESETN
INTRN
X1/CLK
X2
4
BUS BUFFER
OPERATION CONTROL
ADDRESS
DECODE
R/W CONTROL
INTERRUPT CONTROL
IMR
ISR
TIMING
BAUD RATE
GENERATOR
CLOCK
SELECTORS
COUNTER/
TIMER
XTAL OSC
CSR
ACR
CTL
DATA CHANNEL
16 BYTE TRANSMIT
FIFO
TRANSMIT
SHIFT REGISTER
16 BYTE RECEIVE
FIFO
MRA0, 1, 2
CRA
SRA
INPUT PORT
CHANGE OF
STATE
DETECTORS (4)
OUTPUT PORT
FUNCTION
SELECT LOGIC
OPCR
TxDA
RxDA
IP0-IP5
OP0-OP7
V CC
V SS
CONTROL TIMING INTERNAL
DA
T
ABUS
IPCR
ACR
OPR
CTU
8
6
WATCH DOG TIMER
RECEIVE SHIFT
REGISTER
SD00703
IVR
DACKN
IACKN
Figure 2. Block Diagram (68XXX mode)