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Altera_Forum
Honored Contributor
13 years agoI was using PowerPlay last week and also have trouble with getting reasonable numbers from Quartus.
Attached is a PDF of measured power consumption from the DE0-nano board. The board was configured with a Qsys system containing a UART-to-Avalon-MM bridge and a slave interface to a power dissipation block. The power dissipation block contained either toggle registers or counters. The registers/counters could be enabled in blocks. The design had 128-bits of control, allowing power dissipation to be increased in ~1% steps. In the attached figure, 8-bits of registers were enabled for each step. The measurements reflect the fact that wider counters have lower average toggle rates, and hence lower average power dissipation. I tried getting Quartus (11.1sp1) to give me reasonable estimates on power dissipation, however, the toggle rates estimated for the counters were inconsistent with the measurements. I tried getting .VCD measurements for a large design, but after 10 hours of Modelsim-SE simulation time, I needed to use the PC for another job, so killed the simulation. I plan on revisiting this testing on a faster machine and on a DE4 in the next week or so. I know it doesn't really answer your questions, however, I wanted to let you know that you are not alone in your frustration :) Cheers, Dave