Norm/Ken, I modified the Verilog code in my directory (use dcam to run) so that the "vector eater" stops the *pbus* clock after it goes high. Ken, the clock assignment in chip1.edf.v[.b] needs to be slightly different: clk=p25 | !system.U5.vector_enable; The tests I ran worked. Please let me know if there are any more problems. Doug