72F521 - SCI transmit

[seeguard]

Posted on December 04, 2003 at 12:49

72F521 - SCI transmit

[seeguard]

Posted on December 03, 2003 at 08:35

I use the indART-stx debugger. I transmit 1 byte value 0x41 via SCI TX driver.In the EasyComm-test line application on PC, I see a wrong value (not 0x41).

In SCOP I see start bit,0x41, stop bit, but I measure

bit duartion of 128 usec (7.813Khze) the SCIBRR=0xC0; I use the embedded frequancy command 8Mhz in the indART ST7 configuration.

I'd like to know what is the real fCPU I am using with this debugger

and to fix the baud rate to 104 usec bit time (9.6 kHz).

does it possible with the indART debugger (maybe use EXT OSC) ?

atz

[kr]

Posted on December 04, 2003 at 02:10

I hope you are aware of this, if your fOSC is 8MHZ, then your fCPU will be 4 MHz, the inDART STX will provide you 8MHz fOSC only, so please check your calculation.

With 4MHZ fCPU and with TR = 2; PR = 13 will give 9600 baudrate ( SCIBRR = 0xc8 )

You can use external oscillator also, inthat case check the corresponding register values.

If you have any doubt about the CPU frequency use MCO pin to checkout the frequency of CPU.

[seeguard]

Posted on December 04, 2003 at 12:49

hi krsel.

I'd like to thank you very much for your help.

I'm using Fosc=8M external source, configure to 9600 baud(SCIBRR=0xC

. It works!

atz