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Altera_Forum
Honored Contributor
16 years agodata error!help
look at the picture,why CpuData is wrong,but RdBuf is right,
assign CpuData = ( CpuDataVld &HRCW_over_flag )? {8'h00,CpuDataOut} : 16'hzzzz ; assign RdBuf = ( CpuDataVld &HRCW_over_flag )? CpuDataOut : 8'hzz ; note:1.cpudata is a bidirection port,but rdbuf is a reg; 2.clock is 66mhz 3.the picture is a signaltap3 Replies
- Altera_Forum
Honored Contributor
--- Quote Start --- Sorry , maybe I was a little too fast. Is your picture a signaltap or a simulation output ? Can you zoom in so that it is possible to see all value ? Kind regards --- Quote End --- Hi, you mentioned that RdBuf is a "reg", but as far as I know you can't use "assign" for reg. assign RdBuf = ( CpuDataVld &HRCW_over_flag )? CpuDataOut : 8'hzz ; CpuData is a Toplevel port ? What is connected to this port ? assign CpuData = ( CpuDataVld &HRCW_over_flag )? {8'h00,CpuDataOut} : 16'hzzzz ; According to your assignment CpuData is only during CpuDataVld "1" = CpuDataOut. With CpuDataVld "0" you switch back to "z". Maybe somebody is driving the port ? Can you zoom in your traces, in orde to see what values are caaptured ? Kind regards GPK - Altera_Forum
Honored Contributor
--- Quote Start --- Hi, is your Signaltap capture clock synchronous to the data you try to capture ? Kind regards GPK --- Quote End --- Sorry , maybe I was a little too fast. Is your picture a signaltap or a simulation output ? Can you zoom in so that it is possible to see all value ? Kind regards - Altera_Forum
Honored Contributor
--- Quote Start --- look at the picture,why CpuData is wrong,but RdBuf is right, assign CpuData = ( CpuDataVld &HRCW_over_flag )? {8'h00,CpuDataOut} : 16'hzzzz ; assign RdBuf = ( CpuDataVld &HRCW_over_flag )? CpuDataOut : 8'hzz ; --- Quote End --- Hi, is your Signaltap capture clock synchronous to the data you try to capture ? Kind regards GPK