t2
PDATA<7:0>
t1
t5
t6
nACK
t4
t3
t4
nAUTOFD
FIGURE 18 - ECP PARALLEL PORT REVERSE TIMING
NAME
DESCRIPTION
MIN
0
TYP
MAX
UNITS
ns
t1
t2
t3
PDATA Valid to nACK Asserted
nAUTOFD Deasserted to PDATA Changed
0
ns
nACK Asserted to nAUTOFD Deasserted
(Notes 1,2)
80
200
200
ns
t4
t5
t6
nACK Deasserted to nAUTOFD Asserted (Note 2)
nAUTOFD Asserted to nACK Asserted
80
0
ns
ns
ns
nAUTOFD Deasserted to nACK Deasserted
0
Note 1: Maximum value only applies if there is room in the FIFO and terminal count has not been
received. ECP can stall by keeping nAUTOFD low.
Note 2: nACK is not considered asserted or deasserted until it is stable for a minimum of 75 to 130
ns.
189
SMSC [ SMSC CORPORATION ]
