Technical information

SCI to SPI Peripheral Communication in V850ES Microcontrollers

#if (TEMP_DEBUG == 1)

int i;

/* set up continuous select, 1 buffer mode of operation */

ADM = 0x00; /* clear to reset value to stop converter and

generator */

/* also sets select mode, normal conversion,

14.4 us conversion time */

ADMK = 1; /* mask interrupt */

ADS = 0x00; /* no edge detect, software trigger, select ANI0 */

ADCS2 = 1; /* set ADCS2 (ADM.0) to enable reference voltage

generator */

/* delay 14 microseconds; 1 NOP takes 50 nanoseconds at 20 MHz, */

/* so we need to do 20 NOPs per microsecond; 14 x 20 = 280 = 28 x 10 */

for (i = 0; i < 28; i++) {

__asm("nop");

}

ADCS = 1; /* set ADCS (ADM.7) to enable conversion */

#else

TEMP1_CS_OFF; /* deselect chips to allow conversion */

TEMP2_CS_OFF;

CSI00_Init(); /* initialize the CSI00 interface */

/* for Temp Sensor 1 (MAX6627), no further initialization necessary */

/* for Temp Sensor 2 (DS1722), set configuration */

CSI00_SetType3(); /* set CSI00 interface for Type 3

transfer */

TEMP2_CS_ON; /* select chip to enable writing */

/* delay 400ns between CS true and SCK rise */

/* one NOP takes 50ns at 20MHz, so do eight */

__asm("nop"); __asm("nop");

txbuf[0] = 0x80; /* address set to write configuration register

txbuf[1] = 0xE0 | /* top three bits 111 */

0x00 | /* bit 4 = 0, 1SHOT is off */

0x04 | /* bits 3-1 = 010 for 10-bit accuracy, 0.3 sec

conversion time */

0x00; /* bit 0 = 0, SD shutdown bit is off, do continuous

conversion */