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Altera_Forum's avatar
Altera_Forum
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11 years ago

system console, external memory, multiple masters

Hi guys Im fairly new here. Im working with a cyclone V GX board and have used qsys to add a memory controller in my nios code to control some lpddr memory on the eval board. Im u...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

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So i quickly tried

alt_u16 divisorSetting = IORD_ALTERA_AVALON_UART_DIVISOR(UART_0_BASE);

and that spit out 5208 so doing that math, my baud rate would be 9600

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You have not clearly stated (to me) your "real" problem. You've got two possibilities;

1. The Qsys UART baud rate is wrong.

Diagnostic: probe the Qsys UART transmit signal using SignalTap II and calculate the actual baud rate. Is is correct?

2. The FTDI USB-to-UART is wrong.

Diagnostic: probe the Qsys UART receive signal using SignalTap II and calculate the actual baud rate. Is is correct?

Its highly unlikely that the FTDI transmit signal (Qsys UART receive signal) is wrong if you have configured the baud rate in Putty correctly, but you should confirm that. For example, perhaps you assumed your board has a 50MHz clock, when in fact it has a different frequency. If your SignalTap II instance is using the same clock, then the captured trace timing will appear incorrect.

Cheers,

Dave