Re: [Fx2lib-devel] Change sync delay macro (Daniel O'Connor)
Status: Beta
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From: Daniel O'C. <doc...@gs...> - 2011-03-02 22:15:27
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On 02/03/2011, at 4:11, -t wrote: > Hi, > I modified SYNCDELAY to match the Cypress version - this is useful because GPIF designer generates code which calls it and it's a pain to re-edit the file each time you change your design. > > ---> Hi Daniel, sync delay is used in more places that just GPIF implemenations. Various registers are gated by different clock domains. When the CPU writes to these specific registers the contents may not be updated if the sync delay is not executed. The amount of delay is dependent on the two main clock domains. All the details of sync delay can be reviewed in the Cypress TRM. This one originally had me scratching my head for several days... Hope this helps :) <--- I understand that, however when you generate a file with GPIF designer it uses SYNCDELAY; vs fx2lib's SYNCDELAY(); My change alters the calling convention to match Cypress so you don't have to edit the generated file each time. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C |