Hi Group,
I am having an issue getting the SPI on Port C to work on the XmegaA3BU-Xplained to work.
I started with an Atmel example program (ADC_EXAMPLE1_GFX1) so I could display values on the LCD.
This worked just fine.
Then I added some simple code for the SPI which I cannot get to work.
I write to Port C; the SS signal toggles; the LEDs also blink; but the SPI does nothing.
The values read back from the SPI registers are 0.
It's almost like I am not accessing the SPI Port.
Please tell me what I am doing wrong, I am sure I applied something incorrectly.
The program is below.
Thanks for your help and suggestions.
Paul
/*******************************************************************************
*
* ADC Test v2
*
* Created: 6/30/2017 7:33:47 AM
* Author: Paul A. Teseny
* Company: Scaletron Industries, LLC
*
* Processor: ATxmega256A3BU
* Board: Xmega-A3BU Xplainned
*
* This program reads 24 bit data from the LT2400 ADC using the
* SPI interface then it writes it on the integrated LCD screen.
*
* This software is based on the ADC_Example1_GFX1 example from Atmel.
*
******************************************************************************/
#include <asf.h>
#include <stdio.h>
/********!*********!*********!*********!*********!*********!*********!*********!
* Hardware defines
********!*********!*********!*********!*********!*********!*********!*********/
#define SPI_SS_bm 0x10 /* Bit mask for the SS pin. */
#define SPI_MOSI_bm 0x20 /* Bit mask for the MOSI pin. */
#define SPI_MISO_bm 0x40 /* Bit mask for the MISO pin. */
#define SPI_SCK_bm 0x80 /* Bit mask for the SCK pin. */
/* SPI master status code defines */
#define SPI_OK 0 /* The transmission completed successfully. */
#define SPI_INTERRUPTED 1 /* The transmission was interrupted by another master. */
#define SPI_BUSY 2 /* The SPI module is busy with another transmission. */
/* Size of the string output to the display */
#define OUTPUT_STR_SIZE 32
#define NUM_BYTES 4
/*******************************************************************************
* Global Variables
*********!*********!*********!*********!*********!*********!*********!*********/
char out_str[OUTPUT_STR_SIZE] ;
uint16_t paul = 0x2A ;
uint16_t joe = 0x3C ;
uint16_t herman = 0x4D ;
/* Test data to send from master. */
uint8_t masterSendData[NUM_BYTES] = {0x10, 0x20, 0x30, 0x40} ;
/* Data received from slave. */
uint8_t masterReceivedData[NUM_BYTES] ;
/********!*********!*********!*********!*********!*********!*********!*********!
* Program Start
********!*********!*********!*********!*********!*********!*********!*********/
int main(void)
{
board_init() ;
sysclk_init() ;
sleepmgr_init() ;
irq_initialize_vectors() ;
cpu_irq_enable() ;
gfx_mono_init() ;
/* Turn ON the LCD Back light */
ioport_set_pin_high(LCD_BACKLIGHT_ENABLE_PIN) ;
/* Make Port C Bit 6 an Input */
PORTC_DIRCLR = SPI_MISO_bm ;
/* Make Port C Bits 7, 5, 4 Outputs */
PORTC_DIRSET = SPI_SCK_bm | SPI_MOSI_bm | SPI_SS_bm ;
/* Make Port C Outputs have pullups */
PORTC_PIN4CTRL = PORT_OPC_PULLUP_gc ; // !SS
PORTC_PIN5CTRL = PORT_OPC_PULLUP_gc ; // MOSI
PORTC_PIN7CTRL = PORT_OPC_PULLUP_gc ; // SCK
/* Setup SPI on Port C */
SPIC_CTRL = SPI_ENABLE_bm | SPI_MASTER_bm | SPI_MODE_0_gc | SPI_PRESCALER_DIV128_gc ;
/* Setup stuff to display */
paul = PORTC_DIRSET ;
joe = SPIC_CTRL ;
herman = SPIC_STATUS ;
/* Display Values */
snprintf(out_str, OUTPUT_STR_SIZE, "Paul: %6X \n", paul) ;
gfx_mono_draw_string(out_str, 0, 0, &sysfont) ;
snprintf(out_str, OUTPUT_STR_SIZE, "Joe: %6X \n", joe) ;
gfx_mono_draw_string(out_str, 0, 10, &sysfont) ;
snprintf(out_str, OUTPUT_STR_SIZE, "Herman: %6X \n", herman) ;
gfx_mono_draw_string(out_str, 0, 20, &sysfont) ;
/********!*********!*********!*********!*********!*********!*********!*********!
* Program Loop
*
* Write a byte to the SPI on Port C
********!*********!*********!*********!*********!*********!*********!*********/
while (1)
{
/* PHASE 1: Send individual bytes out SPI */
for(uint8_t i = 0; i < NUM_BYTES; i++)
{
LED_Toggle (LED0_GPIO) ;
/* MASTER: Pull SS line low */
PORTC_OUTCLR = PIN4_bm ;
/* Slow it down to see what is happening */
delay_us (5) ;
/* MASTER: Transmit data from master */
SPIC_DATA = masterSendData[i] ;
// while(!(SPIC_STATUS & (1<<7))) ;
/* Slow it down to see what is happening */
delay_us (5) ;
/* MASTER: Release SS to slave. */
PORTC_OUTSET = PIN4_bm ;
/* Slow it down to see what is happening */
delay_ms (10) ;
} /* End of Phase 1 */
LED_Toggle (LED2_GPIO) ;
} /* End of Program Loop */
} /* End of MAIN */
/********!*********!*********!*********!*********!*********!*********!*********!
* That's all folks!
********!*********!*********!*********!*********!*********!*********!*********/
