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transfers from LINK to VME, but mandatory for VME to LINK. LINK will ignore any
writes until the appropriate flag bit is set. The VME may simply scan its inbound data
area and use or ignore the flags as it sees fit.
0(025< &21),*85$7,21
The memory configuration allows for some combination of up to 96 each of bits,
bytes, or words to be transferred from each device to the other. The actual total
number of parameters is limited by the configuration space available. For VME to
LINK transfers, eight unique bits may be stored at locations $000 through $00B for a
total of 96 unique bits. 96 sequential locations are provided between $00C and $06B
for bytes, and 192 sequential locations are provided between $06C and $12B for 96
words. An identical set of memory locations exist for LINK to VME transfers.
Flag bits correspond to the associated data bit, byte, or word in bit-logical order,
hence bit zero of the first flag byte points to the first of the 96 entities. Bit zero of the
second flag byte points to the ninth of the 96 entities, and so forth. Logically, there is
a one to one correlation between flag bits and the bit data area as shown below.
Throughout this discussion, the "first" entity is referred to as bit 0, byte 0 or word 0.
Figure 1 defines the flag bits that correspond to the first eight data bits for bit transfers
from VME to LINK. By logical extension, the Flag byte at $259, bit 0 refers to data
bit 8 at address $001.
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