FPGA上でソフトコアCPUを動かす手引き（ソースコード）

連載「MAX 10 FPGAで学ぶFPGA開発入門」の第6回、「FPGA上でソフトコアCPUを動かす手引き」のソースコードです。

» 2016年09月09日 10時00分 公開
[PR／MONOist]
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・FPGA上でソフトコアCPUを動かす手引き

  1. List 1:
  2. /*
  3.  * main.c
  4.  *
  5.  *  Created on: Oct 29, 2014
  6.  *      Author: apanneer
  7.  */
  8.  
  9.  
  10. //#include "stdio.h"
  11. #include "system.h"
  12. #include "sys/alt_irq.h"
  13. #include "altera_avalon_timer_regs.h"
  14. #include "altera_avalon_pio_regs.h"
  15. #include "altera_modular_adc_sequencer_regs.h"
  16.  
  17.  
  18.  
  19. alt_u8 celsius_lookup(int adc_avg_in);
  20.  
  21. int main()
  22. {
  23.  
  24. 	int switch_datain;
  25.  
  26. 	volatile int adc_avg=0 ,i;
  27. 	printf("*******PIO and On-Die Temp Sensor example********\nChange Switches 1,2, and 3 to change LEDs 1,2 and 3\nThe value of ADC Channel connected to Temperature Sensing Diode is collected every second and is averaged over 64 Samples\n------------------------------------------------------------------------------------------------------");
  28.  
  29.  
  30. 	//Starting the ADC sequencer
  31. 	IOWR(MODULAR_ADC_0_SEQUENCER_CSR_BASE, 0, 0);
  32. 	usleep(10);
  33. 	IOWR(MODULAR_ADC_0_SEQUENCER_CSR_BASE, 0, 1);
  34.  
  35. 	//Event loop never exits
  36. 	while(1)
  37. 	{
  38. 		// Reads the value from Switch and Displays in the LED
  39. 		switch_datain = IORD_ALTERA_AVALON_PIO_DATA(SW_IO_BASE);
  40. 		IOWR_ALTERA_AVALON_PIO_DATA(LED_IO_BASE,switch_datain);
  41. 		//Giving a 1 Second delay
  42. 		usleep(1000000);
  43.  
  44. 		adc_avg=0;
  45. 		//Getting an average of 64 samples
  46. 		for (i=0;i<64;i++)
  47. 		{
  48. 			int adc_value=IORD(MODULAR_ADC_0_SAMPLE_STORE_CSR_BASE,i);
  49. 			adc_avg=adc_avg+adc_value;
  50. 		}
  51.  
  52. 		printf("\nOn-die temperature = %d",(celsius_lookup(adc_avg/64-3417)-40));
  53.  
  54. 	}
  55. 	return 0;
  56. }
  57.  
  58.  
  59.  
  60.  
  61. alt_u8 celsius_lookup(int adc_avg_in)
  62. {
  63. 	 const alt_u8 celsius_lookup_table[383]={
  64. 			165,165,165,164,164,164,163,163,163,162,162,162,161,161,161,160,160,160,
  65. 			159,159,159,158,158,158,157,157,157,156,156,156,155,155,155,154,154,154,
  66. 			153,153,152,152,152,151,151,151,150,150,150,149,149,149,148,148,148,147,
  67. 			147,147,146,146,146,145,145,144,144,144,143,143,143,142,142,142,141,141,
  68. 			141,140,140,140,139,139,138,138,138,137,137,137,136,136,136,135,135,135,
  69. 			134,134,133,133,133,132,132,132,131,131,131,130,130,129,129,128,128,128,
  70. 			128,127,127,126,126,126,125,125,125,124,124,124,123,123,122,122,122,121,
  71. 			121,121,120,120,119,119,119,118,118,118,117,117,116,116,116,115,115,114,
  72. 			114,114,113,113,113,112,112,111,111,111,110,110,109,109,109,108,108,107,
  73. 			107,107,106,106,105,105,105,104,104,103,103,103,102,102,101,101,101,100,
  74. 			100,99,99,99,98,98,97,97,96,96,96,95,95,94,94,94,93,93,92,92,91,91,91,90,
  75. 			 90,89,89,88,88,88,87,87,86,86,85,85,85,84,84,83,83,82,82,82,81,81,80,80,
  76. 			 79,79,78,78,78,77,77,76,76,75,75,74,74,73,73,73,72,72,71,71,70,70,69,69,
  77. 			 68,68,67,67,67,66,66,65,65,64,64,63,63,62,62,61,61,60,60,59,59,58,58,57,
  78. 			 57,56,56,55,55,55,54,54,53,53,52,52,51,51,50,50,49,49,48,48,47,47,46,46,
  79. 			 45,45,44,43,43,42,42,41,41,40,40,39,39,38,38,37,37,36,36,35,35,34,34,33,
  80. 			 33,32,31,31,30,30,29,29,28,28,27,27,26,26,25,24,24,23,23,22,22,21,21,20,
  81. 			 20,19,18,18,17,17,16,16,15,15,14,13,13,12,12,11,11,10, 9, 9, 8, 8, 7, 7,
  82. 			  6, 5, 5, 4, 4, 3, 2, 2, 1, 1, 0 };
  83.  
  84. 	//printf("temp = %d",adc_avg_in);
  85. 	return (celsius_lookup_table[adc_avg_in]);
  86.  
  87. }
  88.
List1

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