AR# 12339: 3.1i NGDBuild - "ERROR:Pack - Unable to pack the following symbols concurrently into an empty IOB component..."
AR# 12339
3.1i NGDBuild - "ERROR:Pack - Unable to pack the following symbols concurrently into an empty IOB component..."
Description
Keywords: NGDBuild, unable, pack, symbols, empty
Urgency: Standard
General Description: My design (which targets a Spartan-II device) does not have any IBuffers instantiated in the VHDL code and has two locked global clock nets in order to perform normal input functions. When I implement, the following error is reported:
"ERROR:Pack - Unable to pack the following symbols concurrently into an empty IOB component: PAD symbol "AddressBus<12>.PAD" (Pad Signal = AddressBus<12>) BUF symbol "C_AddressBus<12>" (Output Signal = N_AddressBus<12>) The symbol AddressBus<12>.PAD has a constraint (LOC=P185) that specifies an illegal physical site for the component. Please correct the constraint value."
Solution
To avoid this error, instantiate IBUFGs on the two locked global clock nets.