Spectrum Brands Quad C6x VME64 - Manual (Page 67)

Spectrum Signal Processing Monaco Technical Reference
Registers
Part Number 500-00191 55
Revision 2.00
ID Register
Address: 016D 801Ch
D31.. ..D8
Reserved
D7.. ..D4 D3 D2 D1 D0
Reserved Node D Node C Node B Node A
This register allows DSP software to identify which processor it is running on. Each of
the four bits in the register correspond to a particular processor node. A node can read
the status of all four bits but can only write to its own bit.
To identify its processor, the DSP program first locks the Global Shared Bus for its use
by asserting TOUT0. It then reads the value of this register and stores the result. This
value is toggled (inverted) and written back to the register. The register is read once
again and compared to the first reading to determine which bit was changed by the write
operation. Because only the bit corresponding to the node can be changed, this bit will
identify the node that the application is running on. TOUT0 should then be de-asserted to
release the Global Shared Bus.