Aim AMC429, Справочное руководство

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18 Software Library Reference Manual for VME 429
Section 2 – Library Administration Functions
' ' C C I I L L P P ' '
Transmit operation current instruction list pointer (when INT or INDI bit is set in the
transmit- or skip instruction control word).
The TX Data Buffer Base Address location contains a 24-bit address pointer
indicating the start of the transmit data buffer which is described with the
following picture.
T
h
e
Label Data locations contains the 31-bit ARINC dataword with the MSB set
to zero or a 32-bit dataword. The first word is called the Buffer Header
Word and is described below.
Interrupt Index : If the value contained in this 10 bit field is identical with
the value in the Current Index field, an Index Interrupt is
asserted in addition to the index reload interrupt if
enabled in the transfer instruction word (INDI Bit).
Index Reload : If the Current Index is decremented to zero this 10 bit
value is loaded into the Current Index field.
Current Index : If not zero the 10 bit Current Index field is decremented
after each access to the data buffer. If the last buffer is
filled (Current Index reaches zero) the current index is
loaded with the value of the Index Reload field.
SID : If this Bit is set to one the index operation is suspended.
Transmit data is fetched from the current index and no
index operation is performed (Current index not modified
and no index interrupts generated).
DIS: Discrete Transfer Mode is selected. This mode allows the
user an unique discrete data location from all transmitters
from one BIU. All or individually masked data bits of the
'
Discrete Register ' can be transmitted with individual
labels. In this mode the transmitted label is build as
follows:
Bits 7 to 0: Label Number Taken from Bits 7 to 0 of this Word.
Bits 31 to 8: ' Discrete Register ' from System Control Block masked
with bits 31 to 8 of this word.
TX
Instruction List Pointer
Reserved
Res.
TX Data Buffer
Base Address
Longword 1
Longword 2
Transfer Instruction
23 0
Interrupt Index Index Reload Current Index
Last Label Data Word
Label Data
First Label Data Word