UART signal does not received

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Anonymous
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Hello Friends, 

   

You are always in busy with Creator3.0, I presume.

   

Anyway, listen to my trouble of PSoC1.

   

  

   

UART signal that sent from PSoC1(8C24233) to (FTK3270/MTF Board 8C21434) was not received.

   

receive interrupt has not occur.

   

UART-Tx signal was lift up 1.7V (look wave1)

   

  

   

Sender is strong drive and receiver is High-Z input.

   

Even if resistive pull-down and pre-buffered by DigBuf 

   

was not for help it.

   

  

   

For an experiment, No load output (look wave2)

   

It seems properly.

   

Any suggestion in owe you. 

   
        
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Bob_Marlowe
Level 10
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First like given 50 questions asked 10 questions asked
        And the cause was?   
Connecting Tx to an output?   
   
Bob   

View solution in original post

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Anonymous
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 WAVE2

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Anonymous
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 Everytime, I have notice the cause when I post it.

   

Also mean to say, this forum will help.

   

How silly, how careless, how fooling. 

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Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked
        And the cause was?   
Connecting Tx to an output?   
   
Bob   
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Anonymous
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 Hello

   

No, wiring is correct but

   

It is just as you see, signal voltage was lifted up

   

8C24223 Device is working 3.3V and 21434 is 5V.

   

 

   

This device is general purpose, LCD display console,

   

Have to work 3.3V signal and 5V signal.

   

And have Rx and Tx also.

   

I have to consider a proper Level-Converter. 

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Anonymous
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        Hello. Let you show Today's Strangeness   
To probe the UART signal, It is too fast.   
I want to get 9,600bps UART signal but It seems 1,562,500bps   
Actual bit period is measured 640ns.   
   
My thought is SysClock=24MHz, VC1=24/12=2MHz, VC3=2000/26=77KHz   
and 77000/8=9600bps   
Channel 2 is actual VC3 pulse.   
   
What was wrong?   
Whatelse wrong setting?   
???   
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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Take a look at this -

   

 

   

http://www.cypress.com/?rID=39848

   

 

   

Regards, Dana.

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Anonymous
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        Aha, Dana-san thanks to informative page,   
I got a cause.   
Clock synchronize setting of UART was set to "Use SysClk Direct"   
This is bad.   
Data Sheet said...   
[   
Use when a 24 MHz (SysClk/1) clock is desired.   
This does not actually perform synchronization   
but provides low-skew access to the system clock itself.   
If selected, this option overrides the setting of the Clock parameter, above.   
It should always be used instead of VC1, VC2, VC3 or Digital Blocks   
where the net result of all dividers in combination produces a 24 Mhz output   
]   
SysClock override all digital block and VC1-3   
I can't understand what is use for this setting.   
Other synchronize option are all OK.   
Thank you.   
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Anonymous
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        Hello   
To pass constant char address is bad.   
It seems a random data or random address was pass through   
On 8C21434, that have 512Byte SRAM (Large memory model)   
Enable paging option and   
Treat const as RAM option not for help   
Do you think what is wrong?   
   
///////////////////////////////////////////////////////   
static char buf[32];   
void SubTest( const char* str )   
{   
//... cstrcpy( buf, "TEST" ); <--- this is good   
... cstrcpy( buf, str ); <--- this is BAD   
... UART_Send( buf ); <--- think like as LCD_PrString();   
}   
///////////////////////////////////////////////////////   
void main()   
{   
... SubTest(" Test "); <--- call from here   
}   
///////////////////////////////////////////////////////   
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Anonymous
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        That was not occur on another device, ever   
C24223 (small memory model)   
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Anonymous
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 It is so simple, You can't believe in it

   

But Fact is Fact.

   

Still not resolve.

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Anonymous
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        I have to correct previous post (Last 04 Oct)   
This trouble happen every PSoC1 devices   
C21434, C24233, C27433 also C29466   
It seems, might be ImageCraft compiler/Linker Bug.   
I have a new evidence   
I have update the compiler,   
V7.05 to V8.05 Pro-DEMO (What's DEMO??)   
but nothing for help ... orz   
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Anonymous
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        Oh! I got a progress   
I had overlooked the small warning message.   
It seems to affect the reference of a constant-character decisively.   
So on, I can work it out.   
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