Hello,
I'm using IAR embedded Workbench for ARM 6.30 kickstart to program a STM32F4 DISCOVERY microcontroler.
I have two problem with ADCs:
- I use two ADC channels (12 & 14) based on the same ADC (ADC2) to 8-bits digitizing two potentiometers output voltages. The trouble is, when I change the first potentiometer value, it's affects the second potentiometer digital value.
- The strangest problem: sometimes when I run my project on the STM32 with the "Make and Restart Debugger" button, with NO CHANGES in my code, the ADC behavior can change: instead of being digitized on 8-bit (0 to 255), potentiometers values will be digitized on 6-bits (0 to 63) or on 16-bits (0 to 65535), I can see it on the watch !! What is the problem with IAR ?
Thanks for your help ! I work on this problem for 2 weeks...
Jean
Note: you can find my ADC initialiation code below:
01.// ADC ADRESS
02.#define ADC_CCR_ADDRESS ((uint32_t)0x40012308)
03.
04.// Table to store digitized ADC values
05.extern __IO uint16_t TabADC[2];
06.
07.
08.////////////////////////////////////////////////////////////////////
09.//////// ADC configuration ///////////
10.////////////////////////////////////////////////////////////////////
11.
12.
13.void ADC_Config(void)
14.{
15.
16. // ADC initialisation
17. ADC_CommonInitTypeDef ADC_CommonInitStructure;
18.
19. // CLOCK set for DMA2 + GPIOC2 + ADC1 + ADC2
20. RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2 | RCC_AHB1Periph_GPIOC, ENABLE);
21. RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_ADC2, ENABLE);
22.
23. // DMA2 config (direct access memory) Stream0 channel0
24. DMA_InitTypeDef DMA_InitStructure;
25. DMA_InitStructure.DMA_Channel = DMA_Channel_0; // USE CHANNEL 0
26. DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&TabADC; // Store in my table the digitized values
27. DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC_CCR_ADDRESS;
28. DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
29. DMA_InitStructure.DMA_BufferSize = 2;
30. DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
31. DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
32. DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
33. DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
34. DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
35. DMA_InitStructure.DMA_Priority = DMA_Priority_High;
36. DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Enable;
37. DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
38. DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
39. DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
40. DMA_Init(DMA2_Stream0, &DMA_InitStructure);
41. DMA_Cmd(DMA2_Stream0, ENABLE); // DMA2_Stream0 enable
42.
43. // ADCs configuration: ADC Channel 12 & 14
44. // POT2: ADC Channel 12 -> PIN PC2
45. // POT3: ADC Channel 14 -> PIN PC4
46.
47. GPIO_InitTypeDef GPIO_InitStructure; // GPIOC
48. GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_4;
49. GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
50. GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_DOWN ;
51. GPIO_Init(GPIOC, &GPIO_InitStructure);
52.
53. // 'ADC "Common"
54. ADC_CommonInitStructure.ADC_Mode = ADC_DualMode_RegSimult;
55. ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div2;
56. ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1;
57. ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_5Cycles;
58. ADC_CommonInit(&ADC_CommonInitStructure);
59.
60. // Initialisation ADC "2" channels 12 & 14
61. ADC_InitStructure.ADC_Resolution = ADC_Resolution_8b;
62. ADC_InitStructure.ADC_ScanConvMode = ENABLE;
63. ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
64. ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
65. ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
66. ADC_InitStructure.ADC_NbrOfConversion = 2;
67. ADC_Init(ADC2, &ADC_InitStructure);
68. // ADC2 regular channels 12, 14
69. ADC_RegularChannelConfig(ADC2, ADC_Channel_12, 1, ADC_SampleTime_3Cycles);
70. ADC_RegularChannelConfig(ADC2, ADC_Channel_14, 2, ADC_SampleTime_3Cycles);
71.
72. // Enable DMA request after last transfer (Multi-ADC mode)
73. ADC_MultiModeDMARequestAfterLastTransferCmd(ENABLE);
74.
75. // Start ADC2
76. ADC_Cmd(ADC1, ENABLE);
77. ADC_Cmd(ADC2, ENABLE);
78.
79. // Start ADC1 Software Conversion
80. ADC_SoftwareStartConv(ADC1);
81.}
Last edited by jeanpri (2012-06-24 13:15:29)
