HI-6120 HOLTIC [Holt Integrated Circuits], HI-6120 Datasheet - Page 75

• Manufacturer Part Number: HI-6120
• Description: MIL-STD-1553 Remote Terminal ICs
• Manufacturer: HOLTIC [Holt Integrated Circuits]

11.2.2. Transmit Mode Command
The transmit mode command data structure contains a Message Information Word, a Time-Tag word and may contain
one Data Word. For mode commands with associated data word (mode codes 16-31 decimal) the host is responsible
for loading the Mode Command Data Table before transmit mode commands are received (e.g., Transmit Vector Word
mode code). Two mode codes have internally generated data words: MC18 “Transmit Last Command” and MC19
“Transmit BIT Word”. For these, the device automatically transmits the data word then copies the transmitted data
value to the stored data structure.
Here is an example data structure for a transmit mode command with data (mode code values 0x10 through 0x1F).
This applies to MC16 “Transmit Vector Word”. Notice that the data pointer points to the data structure starting address,
not the mode data word. The data pointer is located in the transmit mode command’s Descriptor Block, fully described
later:
Bit No.
7,6
4-0
12
11
10
9
8
5
Mnemonic
WCTERR
SYNERR
MERR
WASBSY
ILCMD
-----
BUSID
MC4:0
Function
Word Count Error
This bit is asserted if the command is received without expected mode data word, or with
extra word.
Sync Error.
This bit is asserted when incorrect (command/status) sync type occurs in received mode
data word.
Message Error.
This bit is asserted when message error status change occurs during command process-
ing. See bits 11- 14 for details.
Was Busy Status.
This bit is asserted when the terminal responds to the mode command with BUSY status,
due to global BUSY bit set in 1553 Status Bits Register, or command-specific MKBUSY bit
set in the descriptor table Control Word.
Illegal Command Received.
This bit is asserted when the Illegalization Table bit corresponding to the received com-
mand equals one. The Illegalization Table should only contain nonzero values when
“illegal command detection” is being applied. See section entitled Illegalization Table for
further information.
Not Used.
Bus Identification.
If this bit equals zero, message was transacted on Bus A. If bit equals one, it was trans-
acted on Bus B.
Mode Code.
This 5-bit field contains the mode code extracted from the command word.
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