1553BBC-XX Datasheet, PDF (22/30 Pages) Actel Corporation – Core1553BBC MIL-STD-1553B Bus Controller

Core1553BBC MIL-STD-1553B Bus Controller
Typical BC System
Core1553BBC requires a master CPU to set up the data
tables. The CPU needs to be able to access the internal
core registers as well as the backend memory.
Core1553BBC can be configured in two ways with the
CPU shared memory and with its own memory.
When configured with its own memory, only the CPU
port needs to be connected to the CPU. The CPU accesses
the backend memory via Core1553BBC. This
configuration also supports using an internal FPGA
memory connected to the core and removes the need for
external bus arbitration on the CPU bus.
Alternatively, the core can share the CPU memory as
shown in Figure 9 on page 23. In this case, both the
backend memory and CPU interfaces are connected to
the CPU bus. The core provides control lines that allow
the memory and CPU interfaces to share the same top-
level I/O pins. When in this configuration, the core needs
to read or write the memory it uses MEMREQn and
MEMGNTn signals to arbitrate for the CPU bus before
completing the cycle.
Memory
BUSAINEN
BUSAINP
BUSAINN
BUSAOUTINH
BUSAOUTP
BUSAOUTN
BUSBINEN
BUSBINP
BUSBIN
CPU
BUSAOUTINH
BUSBOUTP
BUSBOUTN
Core1553BBC
Actel FPGA
Figure 8 • Core1553BBC with Its Own Memory
RCVSTBA
RXDAIN
RXDAIN
TXINHA
TXDAIN
TXDAIN
Transceiver
RCVSTBA
RXDBIN
RXDBIN
TXINHA
TXDBIN
TXDBIN
Pulse
Transformer
Pulse
Transformer
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