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| 1 | +#include "i2csniffer.h" |
| 2 | + |
| 3 | +void clear_sniffer_buffers(i2cSniffer* i2c_sniffer) { |
| 4 | + furi_assert(i2c_sniffer); |
| 5 | + for(uint8_t i = 0; i < MAX_RECORDS; i++) { |
| 6 | + for(uint8_t j = 0; j < MAX_MESSAGE_SIZE; j++) { |
| 7 | + i2c_sniffer->frames[i].ack[j] = false; |
| 8 | + i2c_sniffer->frames[i].data[j] = 0; |
| 9 | + } |
| 10 | + i2c_sniffer->frames[i].bit_index = 0; |
| 11 | + i2c_sniffer->frames[i].data_index = 0; |
| 12 | + } |
| 13 | + i2c_sniffer->frame_index = 0; |
| 14 | + i2c_sniffer->state = I2C_BUS_FREE; |
| 15 | + i2c_sniffer->first = true; |
| 16 | +} |
| 17 | + |
| 18 | +void start_interrupts(i2cSniffer* i2c_sniffer) { |
| 19 | + furi_assert(i2c_sniffer); |
| 20 | + furi_hal_gpio_init(pinSCL, GpioModeInterruptRise, GpioPullNo, GpioSpeedHigh); |
| 21 | + furi_hal_gpio_add_int_callback(pinSCL, SCLcallback, i2c_sniffer); |
| 22 | + |
| 23 | + // Add Rise and Fall Interrupt on SDA pin |
| 24 | + furi_hal_gpio_init(pinSDA, GpioModeInterruptRiseFall, GpioPullNo, GpioSpeedHigh); |
| 25 | + furi_hal_gpio_add_int_callback(pinSDA, SDAcallback, i2c_sniffer); |
| 26 | +} |
| 27 | + |
| 28 | +void stop_interrupts() { |
| 29 | + furi_hal_gpio_remove_int_callback(pinSCL); |
| 30 | + furi_hal_gpio_remove_int_callback(pinSDA); |
| 31 | + // Reset GPIO pins to default state |
| 32 | + furi_hal_gpio_init(pinSCL, GpioModeAnalog, GpioPullNo, GpioSpeedLow); |
| 33 | + furi_hal_gpio_init(pinSDA, GpioModeAnalog, GpioPullNo, GpioSpeedLow); |
| 34 | +} |
| 35 | + |
| 36 | +// Called on Fallin/Rising SDA |
| 37 | +// Used to monitor i2c bus state |
| 38 | +void SDAcallback(void* _i2c_sniffer) { |
| 39 | + i2cSniffer* i2c_sniffer = _i2c_sniffer; |
| 40 | + // SCL is low maybe cclock strecching |
| 41 | + if(furi_hal_gpio_read(pinSCL) == false) { |
| 42 | + return; |
| 43 | + } |
| 44 | + // Check for stop condition: SDA rising while SCL is High |
| 45 | + if(i2c_sniffer->state == I2C_BUS_STARTED) { |
| 46 | + if(furi_hal_gpio_read(pinSDA) == true) { |
| 47 | + i2c_sniffer->state = I2C_BUS_FREE; |
| 48 | + } |
| 49 | + } |
| 50 | + // Check for start condition: SDA falling while SCL is high |
| 51 | + else if(furi_hal_gpio_read(pinSDA) == false) { |
| 52 | + i2c_sniffer->state = I2C_BUS_STARTED; |
| 53 | + if(i2c_sniffer->first) { |
| 54 | + i2c_sniffer->first = false; |
| 55 | + return; |
| 56 | + } |
| 57 | + i2c_sniffer->frame_index++; |
| 58 | + if(i2c_sniffer->frame_index >= MAX_RECORDS) { |
| 59 | + clear_sniffer_buffers(i2c_sniffer); |
| 60 | + } |
| 61 | + } |
| 62 | + return; |
| 63 | +} |
| 64 | + |
| 65 | +// Called on Rising SCL |
| 66 | +// Used to read bus datas |
| 67 | +void SCLcallback(void* _i2c_sniffer) { |
| 68 | + i2cSniffer* i2c_sniffer = _i2c_sniffer; |
| 69 | + if(i2c_sniffer->state == I2C_BUS_FREE) { |
| 70 | + return; |
| 71 | + } |
| 72 | + uint8_t frame = i2c_sniffer->frame_index; |
| 73 | + uint8_t bit = i2c_sniffer->frames[frame].bit_index; |
| 74 | + uint8_t data_idx = i2c_sniffer->frames[frame].data_index; |
| 75 | + if(bit < 8) { |
| 76 | + i2c_sniffer->frames[frame].data[data_idx] <<= 1; |
| 77 | + i2c_sniffer->frames[frame].data[data_idx] |= (int)furi_hal_gpio_read(pinSDA); |
| 78 | + i2c_sniffer->frames[frame].bit_index++; |
| 79 | + } else { |
| 80 | + i2c_sniffer->frames[frame].ack[data_idx] = !furi_hal_gpio_read(pinSDA); |
| 81 | + i2c_sniffer->frames[frame].data_index++; |
| 82 | + i2c_sniffer->frames[frame].bit_index = 0; |
| 83 | + } |
| 84 | +} |
| 85 | + |
| 86 | +i2cSniffer* i2c_sniffer_alloc() { |
| 87 | + i2cSniffer* i2c_sniffer = malloc(sizeof(i2cSniffer)); |
| 88 | + i2c_sniffer->started = false; |
| 89 | + i2c_sniffer->row_index = 0; |
| 90 | + i2c_sniffer->menu_index = 0; |
| 91 | + clear_sniffer_buffers(i2c_sniffer); |
| 92 | + return i2c_sniffer; |
| 93 | +} |
| 94 | + |
| 95 | +void i2c_sniffer_free(i2cSniffer* i2c_sniffer) { |
| 96 | + furi_assert(i2c_sniffer); |
| 97 | + if(i2c_sniffer->started) { |
| 98 | + stop_interrupts(); |
| 99 | + } |
| 100 | + free(i2c_sniffer); |
| 101 | +} |
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