Philips Semiconductors Product data sheet
SC28L91
3.3 V or 5.0 V Universal Asynchronous
Receiver/Transmitter (UART)

2004 Oct 21 33

RESETN
tRES

SD00696

RESETN
tRES

80XXX Mode 68XXX Mode

Figure 4. Reset Timing

A0–A3
CEN
tAS
tCS tCH
RDN
tRW tRWD
D0–D7
(READ)
tDD tDF
FLOAT FLOATVALID
NOT
VALID
WDN
tRWD
VALID
D0–D7
(WRITE)
tDS
tDH
tAH

SD00087

NOTE:

Bus action in the 80XXX mode terminates on the rise of CEN, WRN, or RDN which ever one occurs first.

Figure 5. Bus Timing (80XXX mode)