hi-6131pqtf QuickLogic Corp, hi-6131pqtf Datasheet - Page 61

• Manufacturer Part Number: hi-6131pqtf
• Description: Mil-std-1553 / Mil-std-1760 3.3v Bc / Mt / Rt Multi-terminal Device
• Manufacturer: QuickLogic Corp

10.3. Bus Controller General Purpose Queue
The HI-613x BC architecture includes a General Purpose Queue, a 64-word circular stack which the BC can use to
convey information to the external BC host. Various BC instruction op codes push data values onto the queue, such
as the Block Status Word for the last message, Time Tag Counter values, immediate data values, or values stored in
specific RAM addresses.
The BC General Purpose Queue Pointer 0x0038 (see Section 11.8) is initialized with the default starting address
0x00C0 after reset. The queue is relocatable, so the host may overwrite the default base address. Updated by the BC
logic each time a data word is pushed onto the queue, the pointer in register 0x0038 always points to the next storage
address in the queue to be written. The address pointer rolls over every 64th word written. If the BCGPQ bit 13 is logic
1 In the BC Interrupt Enable Register, a BC interrupt is generated when the General Purpose Queue Pointer rolls over
from its ending address to its base address.
10.4. Bus Controller Message Control / Status Blocks
In the BC Instruction List, each occurrence of the “execute message” instructions, XEQ, XQG, XQF and XFG, refer-
ences a MIL-STD-1553B message. The op code word is followed by the parameter word, a memory pointer indicating
the RAM start address for a corresponding Message Control/Status Block. The pointer address indicates the first word
in the Message Control/Status Block, the BC Control Word. Figure 5 illustrates this relationship.
The HI-613x is fully compatible with all MIL-STD-1553B message formats. For most MIL-STD-1553 messages, the
corresponding Message Control/Status Block contains 8 words:
When the message is RT-to-RT, the Message Control/Status Block contains 8 additional words:
Figure 5 shows the range of Message Control/Status Block variations. Selected words in the Message Control/Status
Block are described next.
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BC Control Word. This word contains flags that select message format, choose the active bus, enable message
retry and end-of-message interrupt, indicate expected RT status word flags, etc.
MIL-STD-1553 Command Word. When message is RT-to-RT, this is the Receive Command Word.
Data Address Pointer. For subaddress commands and mode code commands with data, this word identifies
the start address of the Message Data Block in RAM. For mode commands without data, this word is not used.
Time-to-Next Message. The time count loaded here begins decrementing at start of message. When value ex-
ceeds message execution time, it paces delivery of the next message.
Time Tag Word. The current value of the internal time tag count is written to the Time Tag Word at Start-of-Mes-
sage and again at the End-of-Message. When the BC uses a 16-bit time base, this location contains the complete
time count. When the BC uses 32-bit time base, this word contains time bits 15-0 and block word 7 contains time
bits 31-16 (instead of Loopback Word).
Block Status Word. This word contains various message result flags.
Loopback Word, containing the last word transmitted by the BC (16-bit time base only) or
Time Tag Bits 31-16 (32-bit time base only)
RT Status Word received.
This is the Transmit RT Status Word when message is RT-to-RT.
Transmit Command Word.
Receive RT Status Word.
Six unused word locations, to maintain 8 or 16 words per Message Control/Status Block.
HOLT INTEGRATED CIRCUITS
HI-6130, HI-6131
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