HI-3210
Op-Code
Index
Value
ARINC 429 BYTE 1 DESCRIPTOR
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
LSB
LSB
MSB
MSB
ACTION BYTE
VALUE BYTE
Op-Code
000
Index
Value
Description
XXXXX
XXXXXXXX
End of sequence. When op-code 000 is encountered by the sequencer
before it reaches sequence number 255, the sequencer resets to zero and
begins the next transmission cycle starting at descriptor number 0 as soon
as the repitition rate counter rolls over. Note that the descriptor table is
cleared following Master Reset, so no ARINC 429 transmissions are
possible until the sequence table has been configured.
001
XXXXX
XXXXXXXX
No-operation. This descriptor is ignored and the sequencer increments to
the next descriptor in the sequence. This opcode may be used to temporarily
suspend transmission of a particular message in the sequence, without
having to modify the remaining bit fields of the descriptor or reloading the
entire descriptor block in order to delete the entry.
010
011
XXXXX
CCCXX
LLLLLLLL
LLLLLLLL
Immediate data. The value contained in the descriptor value data byte is
1 (the ARINC 429 “label” byte) of the ARINC
loaded into byte
429 label to be transmitted.
Immediate data conditional. The NEWTXn bit corresponding to the ARINC
Data RAM location defined by channel “CCC” and label block “LLLLLLLL” is
read. LLLLLLLL is used as Byte 1 if NEWTXn is set for this or any other
conditional opcode within this descriptor frame. If NEWTXn = 0 for all
conditional op codes (within this descriptor frame) then no transmission
occurs for this frame and the sequencer increments to the next descriptor
frame. The NEWTXn bit for the referencedARINC RAM block is reset.
100
101
CCCBB
CCCBB
LLLLLLLL
LLLLLLLL
Indexed data. The value of ARINC Data RAM location defined by channel
“CCC”, label block “LLLLLLLL” and byte number “BB” is loaded into byte 1 of
theARINC 429 label to be transmitted.
Indexed data conditional. The NEWTXn bit corresponding to the ARINC
Data RAM location defined by channel “CCC”, label block “LLLLLLLL” and
byte number “BB” is read. The corresponding byte is used as Byte 1 if
NEWTXn is set for this or any other conditional opcode within this
descriptor frame. If NEWTXn = 0 for all conditional op codes (within this
descriptor frame) then no transmission occurs for this frame and the
sequencer increments to the next descriptor frame. The NEWTXn bit for the
referencedARINC RAM block is reset.
110
111
XXXX
XXXX
XXXXXXXX
XXXXXXXX
Reserved. Do not use.
Reserved. Do not use.
HOLT INTEGRATED CIRCUITS
23
HOLTIC [ HOLT INTEGRATED CIRCUITS ]
