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GR716-DS-UM, May 2019, Version 1.29
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www.cobham.com/gaisler
GR716
2.9.2
Scenario #2 - Bus bridge
This chapter describes how to configure the I/O mux for a node bus bridge.
The following assumptions are made for the system:
•
External RAM needs to be greater than 128KiB. (If the application needs less than that the inter-
nal on-chip memory should be used in order to utilize the pins on the device more efficiently).
For this example we assume at least 256KiB is needed.
•
Boot from external PROM is required.
•
Connects to spacecraft bus either via 1553B or SpaceWire, and on the other side to node bus via
CAN.
In table 22 two example of I/O configurations for Node bus bridge are shown.
Note that SpaceWire is assumed to be connected on dedicated pins see BRIDGE.CFG1 in table 22. If
SpaceWire redundancy is required configuration BRIDGE.CFG2 in table 22 should be used.