Can't Configure a low frequency clock like say a 10 hz or even 100 hz

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Anonymous
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        Hi,this problem is different from the RTC post, I'm just trying to do a simple debouncer circuit to test an issue. PSOC 3.2 creater PSOC 4M/4200M pioneerkit -44 version System clock is HFCLK48Mhz DEvice selected isCY8C4247AZI-M485 which is what the chip is on the M version of the pioneer kit. When I do a regular clock of say 100 hz, I get this message: Unable to create a divider of 480000 for clock "SwClock." The maximum possible divider for this device is 65536. Too large of or too many clock dividers requested. There is a maximum number of clock dividers (used for digital, analog, and fixed function clocks) available depending on the device selected. I can't change the souce from the HFCLock and I can't change anything in the design wide clock screen to have this clock get its source from the 32khz LFCLK. I know from the datasheet that there are 16 dividers so I don't know why it won't let me create a low frq clock. The examples projects don't work for this pioneer kit ONly earlier kits. I even looked at http://www.cypress.com/blog/psoc-sensei-blog clock example. I tried adding another clock to divide the 48mhz down some, but when I add the second clock, it doesn't give me the first clock as a choice for a source. Only Auto and or HFCLock. Even under the existing tab it doesn't list the first clock So how do I use a really low freq clock like I've seen used onother kits?   
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Bob_Marlowe
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dg,

   

you may configure the WDT to get interrupted @10 or 100 Hz. Would that help you?

   

 

   

Bob

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Bob_Marlowe
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Or, of course, use a TCPWM timer and get interrupted, easier than WDT, but consumes some resources.

   

 

   

Bob

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Anonymous
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        Hi Bob, I can try that, butyeah that consumes additional resources . The issue it seems is this Initially Aligns too settin which I can't change. Its not even listed in the datasheet !?! See attached IT aligns to the 48MH clock ,even with the Source set to auto. So it can't divide down when I do a project for the regular pioneer kit 4200 and build it, I can do a10 Hz, evena 2hz clock because its chaining the dividers. It won't do it with the 4200M Sems like a bit of bug issue to me if I can't change the source.   

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Anonymous
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        Hmma and while this isn't related to the clock bug issue, I just realized the RAspPI header on the -044 kit only has 26 pins. Making it compatible only with the older RaspiPI's. The newer RaspiPi's have 40 pin headers. A design overlook or intentionial? The documentation needs to differentiate between that and not just say compatible with RaspPi.   
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odissey1
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dgallatin95, depending on resources left, you may try adding a chain of DFFs (3-4) to divide clock beyond 65535 to get 100Hz.

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Anonymous
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        Thanks guys! Thouh at first I couldn't get either suggestion to work. Then I found the Freq Divider componet and set it to div 8 a clock singal of 800hz. STill didn't work. I created a clock pin to measure the clock after the Freq Div component and into a TFF that had in between the debouncer and LED and it was at 100 hz. So it wasn't that Then I checked my input pin and realized I was still usiing the Strong Drive for Cmos.        Changed to pull up resistor confiuration and now it works for all   
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ETRO_SSN583
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This approach -

   

 

   

Regards, Dana.

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Anonymous
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        Yes sir. Though I wasn't using the LFCLK, but the 48mhz HFCLk and had it set to 800 hz. Then I had the freq divider set at 8. In a real application,would there a performance difference between using LFCLK vs HFCLk?   
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ETRO_SSN583
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Primarily clock tolerance, Pdiss, jitter tradeoffs.

   

 

   

Regards, Dana.

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Anonymous
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        Right. Gotcha!. Thanks. Can Cypress or a moderator get rid of all those spam post?. Just had to go 3 pages down to find this thread   
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Bob_Marlowe
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Please address to webmaster@cypress.com for removing spam.

   

 

   

Bob

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