Convert energia code from MSP to PIC

[lacint 0]

Hey there,

I do not know if I am writing in the right place. I'm using demo code from TI. You can get this code in this link: https://www.ti.com/technical-documents/mytilit/export-control?litId=SLAC741I&fileType=zip&ref_url=https%3A%2F%2Fwww.ti.com%2Ftool%2FPGA460PSM-EVM&ts=1598270859736

I'm using PGA460PSM-EVM and PIC16F18346. I tested the code with MSP430F2955LP. It works. But I want to use PIC16F18346 with PGA460. And I changed the code for PIC. I have a problem with SPI settings.  I haven't changed the entire code. I just organized the classes according to the C language. I am using CCS C Compiler. I think I cannot adjust the speed in SPI because when I examined it on an oscilloscope using the MSP, I observed the frequency of the received signal as 52.1kHz. When I looked with the PIC, I got the frequency 1.1kHz.

In the demo code, SPI communication is descripted as below:
 

Code:

#include <msp430.h> #include <stdint.h> #include "pga460_spi_430.h" #include <Energia.h> // AW: re-allocate SPI port from B0 to B1 pins static const uint8_t PGA460_SS      = 33;     /* P4.0 */ static const uint8_t PGA460_SCK     = 34;     /* P4.3 */ static const uint8_t PGA460_MOSI    = 10;     /* P4.2 */ static const uint8_t PGA460_MISO    = 9;     /* P4.1 */ #if defined(__MSP430_HAS_USCI_B0__) || defined(__MSP430_HAS_USCI_B1__) || defined(__MSP430_HAS_USCI__) /**  * USCI flags for various the SPI MODEs  *  * Note: The msp430 UCCKPL tracks the CPOL value. However,  * the UCCKPH flag is inverted when compared to the CPHA  * value described in Motorola documentation.  */ #define SPI_MODE_0 (UCCKPH)             /* CPOL=0 CPHA=0 */ #define SPI_MODE_1 (0)                    /* CPOL=0 CPHA=1 */ #define SPI_MODE_2 (UCCKPL | UCCKPH)    /* CPOL=1 CPHA=0 */ #define SPI_MODE_3 (UCCKPL)             /* CPOL=1 CPHA=1 */ #define SPI_MODE_MASK (UCCKPL | UCCKPH) /**  * spi_initialize_pga460() - Configure USCI UCB1 for SPI mode  *  * P2.0 - CS (active low)   // AW --> P4.0 for F5529 (NC on BP)  * P1.5 - SCLK           // AW --> P4.3 for F5529  * P1.6 - MISO aka SOMI    // AW --> P4.2 for F5529  * P1.7 - MOSI aka SIMO    // AW --> P4.1 for F5529  *  */ /* Calculate divisor to keep SPI clock close to 4MHz but never over */ #ifndef SPI_CLOCK_SPEED #define SPI_CLOCK_SPEED 4000000L #endif #if F_CPU < 4000000L #define SPI_CLOCK_DIV() 1 #else #define SPI_CLOCK_DIV() ((F_CPU / SPI_CLOCK_SPEED) + (F_CPU % SPI_CLOCK_SPEED == 0 ? 0:1)) #endif #define SPI_CLOCK_DIV_DEFAULT (F_CPU / 4) void usscSPI_begin(void) {    UCB1CTL1 = UCSWRST | UCSSEL_2;      // Put USCI in reset mode, source USCI clock from SMCLK    UCB1CTL0 = SPI_MODE_0 | UCMSB | UCSYNC | UCMST;  // Use SPI MODE 0 - CPOL=0 CPHA=0     /* Set pins to SPI mode. */    pinMode_int(PGA460_SCK, PORT_SELECTION0 | (PM_UCB1CLK << 8));//SPISCK_SET_MODE);    pinMode_int(PGA460_MOSI, PORT_SELECTION0 | (PM_UCB1SDA << 8));//SPIMOSI_SET_MODE);    pinMode_int(PGA460_MISO, PORT_SELECTION0 | (PM_UCB1SCL << 8));//SPIMISO_SET_MODE);    UCB1BR0 = SPI_CLOCK_DIV() & 0xFF;   // set initial speed to 4MHz    UCB1BR1 = (SPI_CLOCK_DIV() >> 8 ) & 0xFF;    UCB1CTL1 &= ~UCSWRST;             // release USCI for operation } /**  * spi_disable_pga460() - put USCI into reset mode  */ void usscSPI_end(void) {     UCB1CTL1 |= UCSWRST;                // Put USCI in reset mode } /**  * spi_send() - send a byte and recv response  */ uint8_t usscSPI_transfer(const uint8_t _data) {    UCB1TXBUF = _data; // setting TXBUF clears the TXIFG flag    while (UCB1STAT & UCBUSY)       ; // wait for SPI TX/RX to finish    return UCB1RXBUF; // reading clears RXIFG flag } /***SPI_MODE_0  * spi_set_divisor_pga460() - set new clock divider for USCI  *  * USCI speed is based on the SMCLK divided by BR0 and BR1  *  */ void usscSPI_setClockDivider(const uint16_t clkdiv) {    UCB1CTL1 |= UCSWRST;      // go into reset state    UCB1BR0 = clkdiv & 0xFF;    UCB1BR1 = (clkdiv >> 8 ) & 0xFF;    UCB1CTL1 &= ~UCSWRST;      // release for operation } /**  * spi_set_bitorder_pga460(LSBFIRST=0 | MSBFIRST=1)  */ void usscSPI_setBitOrder(const uint8_t order) {     UCB1CTL1 |= UCSWRST;        // go into reset state     UCB1CTL0 = (UCB1CTL0 & ~UCMSB) | ((order == 1 /*MSBFIRST*/) ? UCMSB : 0); /* MSBFIRST = 1 */     UCB1CTL1 &= ~UCSWRST;       // release for operation } /**  * spi_set_datamode_pga460() - mode 0 - 3  */ void usscSPI_setDataMode(const uint8_t mode) {     UCB1CTL1 |= UCSWRST;        // go into reset state     switch(mode) {     case 0: /* SPI_MODE0 */         UCB1CTL0 = (UCB1CTL0 & ~SPI_MODE_MASK) | SPI_MODE_0;         break;     case 1: /* SPI_MODE1 */         UCB1CTL0 = (UCB1CTL0 & ~SPI_MODE_MASK) | SPI_MODE_1;         break;     case 2: /* SPI_MODE2 */         UCB1CTL0 = (UCB1CTL0 & ~SPI_MODE_MASK) | SPI_MODE_2;         break;     case 4: /* SPI_MODE3 */         UCB1CTL0 = (UCB1CTL0 & ~SPI_MODE_MASK) | SPI_MODE_3;         break;     default:         break;     }     UCB1CTL1 &= ~UCSWRST;       // release for operation } #else     //#error "Error! This device doesn't have a USCI peripheral" #endif

In the code I wrote, SPI communication settings are described as below:

Code:

#include "16F18346.h" #device ADC=10 #use delay(internal=16000000) #use spi(DI=PIN_B4, DO=PIN_C7, CLK=PIN_B6, baud=4000000, MODE=2, stream=PGA) #include "PIC16F18346_PIN.h"    uint8 _regdata=0; //extern SPIClass usscSPI; uint8 usscSPI_transfer(uint8 _data) {         // MSB --> LSB /////////////////////////////////////////////////    _data = (((_data & 0b11110000)>>4) | ((_data & 0b00001111)<<4));    _data = (((_data & 0b11001100)>>2) | ((_data & 0b00110011)<<2));    _data = (((_data & 0b10101010)>>1) | ((_data & 0b01010101)<<1));    ////////////////////////////////////////////////////////////////        _regdata = spi_xfer(PGA,_data,8);    // LSB --> MSB /////////////////////////////////////////////////    _regdata = (((_regdata & 0b11110000)>>4) | ((_regdata & 0b00001111)<<4));    _regdata = (((_regdata & 0b11001100)>>2) | ((_regdata & 0b00110011)<<2));    _regdata = (((_regdata & 0b10101010)>>1) | ((_regdata & 0b01010101)<<1));    ////////////////////////////////////////////////////////////////        return _regdata;     } void usscSPI_begin() { } void usscSPI_end() { } void usscSPI_setBitOrder(uint8 bitOrder) { } void usscSPI_setDataMode(uint8 mode) { } void usscSPI_setClockDivider(uint8 rate) { }

 

Where is my fault? How can I increase the frequency?

[zeke 693]

@lacint,

This is a difficult question to answer because the people who hang out here are MSP430 people and not PIC people.

Have you considered asking your questions over at the Microchip forums?

[Rei Vilo 695]

If you're using Energia for the MSP430, you can easily port it to chipKIT as both platforms are supported by the Arduino SDK.

However, you should stick with high-level libraries like SPI and Wire instead of register-level commands.

Please refer to Porting an Arduino library to Energia for some pointers.