cc1101 data rate

Have you tried to export the 500 kbps settings directly from SmartRF Studio?

Yes . Even tried the settings from the expert mode tab there are for 500 kbaud MSK.

I tried the settings with two CC1101 EMs with SmartRF Studio with the 500 kbps settings and I have no issues getting them to communicate. From the information in the post it's not possible to say why you don't get it to work.

these are my settings for 4 FSK 250 kbaud

0x29, // IOCFG2 -- GDO2 Output Pin Configuration
0x2E, // IOCFG1 -- GDO1 Output Pin configuration
0x06, // IOCFG0 -- GDO0 Output Pin configuration
0x07, // FIFOTHR -- RXFIFO and TXFIFO thresholds
0x7A, // SYNC1 -- Sync word, High byte
0x0E, // SYNC0 -- Sync word, Low byte
0x14, // PKTLEN -- Packet length
0x04, // PKTCTRL1 -- Packet automation control
0x05, // PKTCTRL0 -- Packet automation control
0x06, // FSCTRL1 -- Freq.synthesizer control
0x00, // FSCTRL0 -- Freq.synthesizer control
0x21, // FREQ2 -- Frequency Control Word, High Byte
0x62, // FREQ1 -- Frequency Control Word, Middle Byte
0x76, // FREQ0 -- Frequency Control Word, Low Byte
0x0D, // MDMCFG4 -- Modem Configuration
0x3B, // MDMCFG3 -- Modem Configuration
0x46, // MDMCFG2 -- Modem Configuration
0x22, // MDMCFG1 -- Modem Configuration
0xF8, // MDMCFG0 -- Modem Configuration
0x72, // DEVIATN -- Modem Deviation Setting
0x07, // MCSM2 -- Main radio control state Machine configuration
0x30, // MCSM1 -- Main Radio Control State Machine configuration
0x18, // MCSM0 -- Main Radio Control State Machine configuration
0x16, // FOCCFG -- Freq Offset Compensation configuration
0x6c, // BSCFG -- Bit Synchronization configuration
0x43, // AGCCTRL2 -- AGC control
0x49, // AGCCTRL1 -- AGC control
0x91, // AGCCTRL0 -- AGC control
0xFB, // WORCTRL -- Wake On Radio Control
0x56, // FREND1 -- Front end RX configuration.
0x10, // FREND0 -- Front end TX configuration.
0xEA, // FSCAL3 -- Frequency Synthesizer Calibration control
0x2A, // FSCAL2 -- Frequency Synthesizer calibration
0x00, // FSCAL1 -- Frequency Synthesizer calibration
0x1F, // FSCAL0 -- Frequency Synthesizer calibration
0x41, // RCCTRL1 -- RC Oscillator Configuration
0x00, // RCCTRL0 -- RC Oscillator Configuration
0x59, // FSTEST -- Frequency synthesizer calibration
0x7F, // PTEST -- Production Test
0x3F, // AGCTEST -- AGC Test
0x88, // TEST2 -- Various Test settings
0x31, // TEST1 -- Various Test settings
0x09, // TEST0 -- Various Test settings
0xC0 // PATABLE

i m able to receive only garbage data with these settings but at least its not nothing.I gues i have to search in my code for errors ?

Hi again. With these settings i`m able to receive only noice.I get them from SmartRF with parameters shown in the datasheet page 13. 4-FSK, 250 kBaud data rate,254 kHz deviation, 812 kHz digital channel filter bandwidth.If they are not right can someone give me working ones or correct them .I`m not a RF expert and i dont know what i`m doing wrong.I just need to make the CC`s comunicate at high speed.I also have tried the settings from DN036 for 600 kbps.they also dont work for me.Could my problem be hardware  not software?But if it is so how can they work with easy mode settings.

Thanks again in advance

You wrote that you got it to work with the default settings in SmartRFStudio. Have you tried some other datarates with settings taken from Studio?

Do you have any instruments to do measurements? Are you able to check if sending a CW (tone) that your center frequency is as expected? A typical issue is too large tolerance on the xtal or wrong load caps.

Thanks for the suggestion i will check them and no i dont have any instruments other than multimeter