HI-3282
time as EN, the byte will also be placed into the transmitter FIFO.
SEL is then taken high and EN is strobed again to place the upper
byte of the data word on the data bus. By strobing PL2 at the same
time as EN, the second byte will also be placed into the FIFO. The
data word is now ready to be transmitted according to the parity
programmed into the control word register.
In normal operation, either byte of a received data word may be read
from the receiver latches first by use of SEL input. During repeater
operation however, the lower byte of the data word must be read
first. This is necessary because, as the data is being read, it is also
being loaded into the FIFO and the transmitter FIFO is always
loaded with the lower byte of the data word first.
REPEATER OPERATION
The repeater mode of operation allows a data word that has been
received by the HI-3282 to be placed directly into its FIFO for
transmission. After a 32-bit word has been shifted into the receiver
shift register, the D/R flag will go low. A logic "0" is placed on the SEL
line and EN is strobed. This is the same procedure as for normal
receiver operation and it places the lower byte (16) of the data word
on the d a t a bus.
By strobing P L 1 at the same
429DO
ARINC BIT
429DO
DATA
NULL
DATA
NULL
DATA
NULL
BIT 30
BIT 31
BIT 32
WORD GAP
BIT 1
NEXT WORD
DATA BUS
VALID
t
CWSET
t
CWHLD
CWSTR
t
CWSTR
t
D/R
t
END/R
t
EN
t
SELEN
t
ENSEL
t
ENEN
t
DATAEN
t
ENDATA
t
SELEN
t
ENSEL
t
D/REN
DATA BUS
t
DATAEN
t
ENDATA
HOLT INTEGRATED CIRCUITS
6
HOLTIC [ HOLT INTEGRATED CIRCUITS ]
