===Interface with TI microcontroller: the MSP430=== Sample program in C written in the microcontroller MSP430F169 this microcontroller has 2 SPI ports. SPI mode: Single-bit serial 2-wire Mode (default mode) initialization and loading of CSR and CFTW0 records: CSR_ADDRESS int = 0x00; AD9959 CSR adresss Byte CSR_NUM_BYTE int = 0x01; CSR number of byte register long CSR0 = 0x10; AD9959's channel 0 MSB first default SPI FTW_ADDRESS int = 0x04; AD9959 FTW adresss Byte FTW_NUM_BYTE int = 0x04; FTW number of byte register long FTW0 = 0x28F5C28F; frequency in hex cares x2 ^ 32 / fclock in the hand: P4OUT = 0x40; AD9959 master reset MSP430 validation bit P4OUT = 0x00; AD9959 master set of validation bit MSP430 write_serial_port (CSR_ADDRESS, CSR0, CSR_NUM_BYTE); P5OUT = 0x40; I / O update DDS bit validation MSP430 P5OUT = 0x00; I / O update DDS bit validation MSP430 write_serial_port (FTW_ADDRESS, FTW0, FTW_NUM_BYTE); P5OUT = 0x40; I / O update DDS bit validation MSP430 P5OUT = 0x00; I / O update DDS bit validation MSP430 ===Comments on the program=== To initialize the DDS applying this procedure: RESET-DATA_SEND_to_BUFFER-IO_UPDATE. RESET DDS (pin 3), load the data from each register via the SPI port write_serial_port ... then carried out an I / O UPDATE pin 46 of the DDS for validation and data transfer. This program end loads the channel 0 with a frequency of 80MHz and an amplitude default FULL DAC. I / O_UPDATE is synchronous to the SYNC_CLK (Pin 54) = Master clock / 4. See Figure 40 of the DDS datasheet. Below under the boot program of the ports of the microcontroller and the SPI for the MSP430F169 TI provided numerous examples of base codes to configure the SPI modes, I2C and use the Flash memory: slac015p.zip void_init_SPI (void) { BCSCTL1 | = XTS; ACLK = = LFXT1 HF XTAL BCSCTL2 | = SELM_3; MCLK = LFXT1 (safe) pine 8.9 of MSP430 P1SEL = 0x00; P1 I / O select P2SEL = 0x00; P2 I / O select P3SEL = 0x00; P3 I / O select P4SEL = 0x00; P4 I / O select P5SEL = 0x0A; P5.1,3 SPI select option P6SEL = 0x00; P6 I / O select P1DIR = 0xFF; P1.output management P2DIR = 0xFF; P2 output management P3DIR = 0xFF; P3 output management P4DIR = 0xFF; P4 output management P5DIR = 0xFF; P5 output management P6DIR = 0xFF; P6 output management ME2 | = USPIE1; Enable SPI USART1 UCTL1 | CHAR = + SYNC + MM; 8-bit SPI Master ** ** SWRST UTCTL1 CKPH + = + SSEL1 STC; SMCLK delayed, 3-pin UBR01 = 0x2; ACLK / 2 for baud rate UBR11 = 0x0; ACLK / 2 for baud rate UMCTL1 = 0x0; Clear modulation UCTL1 & = ~ SWRST; Initialize USART state machine } BCSCTL1 | = XTS; and BCSCTL2 | = SELM_3; used to be the HF XTAL MSP430 operate at 8MHz instead of 32KHz default. MSP430F169 ----------------- / | \ | XIN | - | | | HF XTAL (455k - 8 Mhz) - | RST XOUT | - | | | P5.4 | -> MCLK XTAL = According to Mr Buccini Texas Instruments Inc. Feb 2005 Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.21a the routine for loading data into SPI mode MSP430F169: write_serial_port void (int instruction, long data, int num_byte) { int i = 0; TXBUF1 = statement; do { TXBUF1 = data >> (num_byte-1-i) * 8; i ++; } while (i > (num_byte-1-i) * 8; num_byte--; } while (! (SSI0_SR_R & SSI_SR_TNF)) { ; } The init routine (SPI) for the ARM TM4C123GH6PM: // Enable Peripheral SSI0 SysCtlPeripheralEnable (SYSCTL_PERIPH_GPIOA); // Enable GPIO port A SSI0. SysCtlPeripheralEnable (SYSCTL_PERIPH_SSI0); GPIOPinConfigure (GPIO_PA2_SSI0CLK); GPIOPinConfigure (GPIO_PA3_SSI0FSS); GPIOPinConfigure (GPIO_PA5_SSI0TX); GPIOPinTypeSSI (GPIO_PORTA_BASE, GPIO_PIN_5 | GPIO_PIN_3 | GPIO_PIN_2); // GPIOPinTypeSSI (GPIO_PORTA_BASE, GPIO_PIN_5 | GPIO_PIN_2); SSIConfigSetExpClk (SSI0_BASE, SysCtlClockGet () SSI_FRF_MOTO_MODE_0, SSI_MODE_MASTER, 10000000, 8); SSIEnable (SSI0_BASE); // Enable the SSI Example of initializing Port B on ARM TM4C123GH6PM: // Void PortB_Init (void) volatile unsigned long delay; SYSCTL_RCGC2_R | = 0x00000002; // 1) activate clock for Port B delay = SYSCTL_RCGC2_R; // Allow for time clock to start GPIO_PORTB_AMSEL_R = 0x00; // 3) disable analog one PB GPIO_PORTB_PCTL_R = 0x00000000; // 4) PCTL GPIO is PB0 GPIO_PORTB_DIR_R | = 0xFF; // 5) PB0-PB7 is out // GPIO_PORTB_AFSEL_R & = ~ 0x01; // 6) disable alt funct on PB0 GPIO_PORTB_AFSEL_R & = ~ 0xFF; // 6) disable alt funct on PB0-PB7 GPIO_PORTB_DEN_R | = 0xFF; // 7) enable digital I / O on PB0-PB7 Example of initializing a USB-PORT for UART0 serial communication on the ARM TM4C123GH6PM: // Void init_UART0 (void) SysCtlPeripheralEnable (SYSCTL_PERIPH_UART0); SysCtlPeripheralEnable (SYSCTL_PERIPH_GPIOA); GPIOPinConfigure (GPIO_PA0_U0RX); GPIOPinConfigure (GPIO_PA1_U0TX); GPIOPinTypeUART (GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1); UARTConfigSetExpClk (UART0_BASE, SysCtlClockGet (), 9600, (UART_CONFIG_WLEN_8 | UART_CONFIG_STOP_ONE | UART_CONFIG_PAR_NONE)); Example of declaration and initialization of the frequency word registers: // // AD9852 FTW0_ADRESS int = 0x02; // Unsigned long long FTW0 = 0x17E4B17E4B1; //1.75MHz@300MHz clk unsigned long long FTW0; // Float FTW0 = 0x17E4B17E4B1; //1.75MHz@300MHz clk FTW0_NUM_BYTE int = 0x06; // // AD9858 FTW1_ADRESS int = 0x03; unsigned long FTW1 = 0x418937; // @ 1000MHz 1MHz clk FTW1_NUM_BYTE int = 0x04; // // AD9858 CFR_ADRESS int = 0x00; unsigned long CFR = 0x79; // MSB first CFR_NUM_BYTE int = 0x04;