74hct7403 NXP Semiconductors, 74hct7403 Datasheet - Page 27

• Manufacturer Part Number: 74hct7403
• Description: 4-bit X 64-word Fifo Register; 3-state
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Note to Fig.23
Sequence 1 (both FIFOS empty, starting SHIFT-IN process)
After a MR pulse has been applied FIFO
valid data being present at the outputs. The DIR flags are set HIGH due to the FIFOs being ready to accept data. SO
is held HIGH and two SI
of FIFO
When SO
HIGH (4).
September 1993
handbook, full pagewidth
4-Bit x 64-word FIFO register; 3-state
SO
DOR B OUTPUT
Q
DIR B OUTPUT
DOR A OUTPUT
Q nA OUTPUT
DIR A OUTPUT
SI
D
MR INPUT
nA
nB
A
Fig.23 Waveforms showing the functionality and intercommunication between two FIFOs (refer to Fig.18).
B
A
INPUT
INPUT
OUTPUT
and to the input stage of FIFO
INPUT
B
goes LOW, the first bit is shifted out and a second bit ripples through to the output after which DOR
sequence 1
A
(1)
pulses are applied (1). These pulses allow two data words to ripple through to the output stage
(3)
(2)
(4)
sequence 2
B
A
(2). When data arrives at the output of FIFO
and FIFO
B
(5)
are empty. The DOR flags of FIFO
(6)
sequence 3
27
(7)
sequence 4
(8)
(9)
(10)
(11)
sequence 5
B
, a DOR
A
and FIFO
74HC/HCT7403
B
pulse is generated (3).
(12)
(13)
Product specification
B
go LOW due to no
sequence 6
MGA687
B
(14)
goes
B