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Altera_Forum's avatar
Altera_Forum
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18 years ago

DSP Builder Error in Runnig

hi folks,

this is my first topic here and i was really stuck in this so please help me

the problem started by having a DDC example from the Altera website and wanted to check it

on my DSP Builder 7.1 but it was designed by 6.1 blocks so i did the conversion to the 7.1

but manually cause the automatic command line to upgrade didn't work for me and after

great efforts in figuring out which is which in the modified parameters names i managed to

complete the blocks but when i did press run i got an error that says:

"illegal rate transition found involving 'm121/cic_clken' at input port 1 and 'm121/Constant' at output port 1. A Rate Transition must be inserted between them."

not only one but many so i was just wondering what is the reason for this

another thing i noticed the input or output ports have a new parameter called specify clock and clock (is this the reason of my problem ????)

attached my model and work so please take a time in checking it out

thanks for ur efforts

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    7.1 completely changed its simulation library and clocking schemes. Typically you now define your system clock rate with a Clock block. Set its rate to 'clock1' as your defined matlab variable. Name the clock block something. 'Clk1' will avoid confusion. Then define the sampling rates of all your inputs by setting their input clock rate to 'Clk1'. Note you need to use the Clock block name, not the Matlab variable.

  • Altera_Forum's avatar
    Altera_Forum
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    18 years ago

    Have you tried to use variable step of discrete solver in your simulation? From your .mdl design, browse to Simulation option, in Configuration Parameters, set Solver Type to Variable Step, Solver Discrete. Does that help?