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Diffstat (limited to 'digital-driver/firmware/TinyWire-master/TinyWireS/examples/attiny85_i2c_analog/attiny85_i2c_analog.ino')
| -rw-r--r-- | digital-driver/firmware/TinyWire-master/TinyWireS/examples/attiny85_i2c_analog/attiny85_i2c_analog.ino | 210 |
1 files changed, 0 insertions, 210 deletions
diff --git a/digital-driver/firmware/TinyWire-master/TinyWireS/examples/attiny85_i2c_analog/attiny85_i2c_analog.ino b/digital-driver/firmware/TinyWire-master/TinyWireS/examples/attiny85_i2c_analog/attiny85_i2c_analog.ino deleted file mode 100644 index 7190c93..0000000 --- a/digital-driver/firmware/TinyWire-master/TinyWireS/examples/attiny85_i2c_analog/attiny85_i2c_analog.ino +++ /dev/null @@ -1,210 +0,0 @@ -/** - * Example sketch for writing to and reading from a slave in transactional manner - * - * NOTE: You must not use delay() or I2C communications will fail, use tws_delay() instead (or preferably some smarter timing system) - * - * On write the first byte received is considered the register addres to modify/read - * On each byte sent or read the register address is incremented (and it will loop back to 0) - * - * You can try this with the Arduino I2C REPL sketch at https://github.com/rambo/I2C/blob/master/examples/i2crepl/i2crepl.ino - * If you have bus-pirate remember that the older revisions do not like the slave streching the clock, this leads to all sorts of weird behaviour - * Examples use bus-pirate semantics (like the REPL) - * - * The basic idea is: - * 1. Choose your ADC channel (0-X), use "byte ch = 1;" for example. - * 2. Combine the channel and conversion start flag to single calue: byte start_on_ch = (ch | _BV(7)); // This is 0x81 - * 3. Write start_on_ch to the first register on the attiny [ 8 0 81 ] - * 4. Come back later and check the first register [ 8 0 [ r ], if the value is same as ch then the conversion is complete, you can now read the value - * 5. read the value [ 8 2 [ r r ] (first one is low, second high byte) - * - * You need to have at least 8MHz clock on the ATTiny for this to work (and in fact I have so far tested it only on ATTiny85 @8MHz using internal oscillator) - * Remember to "Burn bootloader" to make sure your chip is in correct mode - */ - - -/** - * Pin notes by Suovula, see also http://hlt.media.mit.edu/?p=1229 - * - * DIP and SOIC have same pinout, however the SOIC chips are much cheaper, especially if you buy more than 5 at a time - * For nice breakout boards see https://github.com/rambo/attiny_boards - * - * Basically the arduino pin numbers map directly to the PORTB bit numbers. - * -// I2C -arduino pin 0 = not(OC1A) = PORTB <- _BV(0) = SOIC pin 5 (I2C SDA, PWM) -arduino pin 2 = = PORTB <- _BV(2) = SOIC pin 7 (I2C SCL, Analog 1) -// Timer1 -> PWM -arduino pin 1 = OC1A = PORTB <- _BV(1) = SOIC pin 6 (PWM) -arduino pin 3 = not(OC1B) = PORTB <- _BV(3) = SOIC pin 2 (Analog 3) -arduino pin 4 = OC1B = PORTB <- _BV(4) = SOIC pin 3 (Analog 2) - */ -#define I2C_SLAVE_ADDRESS 0x4 // the 7-bit address (remember to change this when adapting this example) -// Get this from https://github.com/rambo/TinyWire -#include <TinyWireS.h> -// The default buffer size, though we cannot actually affect it by defining it in the sketch -#ifndef TWI_RX_BUFFER_SIZE -#define TWI_RX_BUFFER_SIZE ( 16 ) -#endif -// For the ADC_xxx helpers -#include <core_adc.h> - -// The "registers" we expose to I2C -volatile uint8_t i2c_regs[] = -{ - 0x0, // Status register, writing (1<<7 & channel) will start a conversion on that channel, the flag will be set low when conversion is done. - 0x1, // Averaging count, make this many conversions in row and average the result (well, actually it's a rolling average since we do not want to have the possibility of integer overflows) - 0x0, // low byte - 0x0, // high byte -}; -const byte reg_size = sizeof(i2c_regs); -// Tracks the current register pointer position -volatile byte reg_position; -// Tracks wheter to start a conversion cycle -volatile boolean start_conversion; -// Counter to track where we are averaging -byte avg_count; -// Some temp value holders -int avg_temp1; -int avg_temp2; - -/** - * This is called for each read request we receive, never put more than one byte of data (with TinyWireS.send) to the - * send-buffer when using this callback - */ -void requestEvent() -{ - TinyWireS.send(i2c_regs[reg_position]); - // Increment the reg position on each read, and loop back to zero - reg_position++; - if (reg_position >= reg_size) - { - reg_position = 0; - } -} - -/** - * The I2C data received -handler - * - * This needs to complete before the next incoming transaction (start, data, restart/stop) on the bus does - * so be quick, set flags for long running tasks to be called from the mainloop instead of running them directly, - */ -void receiveEvent(uint8_t howMany) -{ - if (howMany < 1) - { - // Sanity-check - return; - } - if (howMany > TWI_RX_BUFFER_SIZE) - { - // Also insane number - return; - } - - reg_position = TinyWireS.receive(); - howMany--; - if (!howMany) - { - // This write was only to set the buffer for next read - return; - } - while(howMany--) - { - i2c_regs[reg_position] = TinyWireS.receive(); - if ( reg_position == 0 // If it was the first register - && bitRead(i2c_regs[0], 7) // And the highest bit is set - && !ADC_ConversionInProgress() // and we do not actually have a conversion running already - ) - { - start_conversion = true; - } - reg_position++; - if (reg_position >= reg_size) - { - reg_position = 0; - } - } -} - - -void setup() -{ - // TODO: Tri-state this and wait for input voltage to stabilize - pinMode(3, OUTPUT); // OC1B-, Arduino pin 3, ADC - digitalWrite(3, LOW); // Note that this makes the led turn on, it's wire this way to allow for the voltage sensing above. - - pinMode(1, OUTPUT); // OC1A, also The only HW-PWM -pin supported by the tiny core analogWrite - - /** - * Reminder: taking care of pull-ups is the masters job - */ - - TinyWireS.begin(I2C_SLAVE_ADDRESS); - TinyWireS.onReceive(receiveEvent); - TinyWireS.onRequest(requestEvent); - - - // Whatever other setup routines ? - - digitalWrite(3, HIGH); -} - -void loop() -{ - /** - * This is the only way we can detect stop condition (http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&p=984716&sid=82e9dc7299a8243b86cf7969dd41b5b5#984716) - * it needs to be called in a very tight loop in order not to miss any (REMINDER: Do *not* use delay() anywhere, use tws_delay() instead). - * It will call the function registered via TinyWireS.onReceive(); if there is data in the buffer on stop. - */ - TinyWireS_stop_check(); - - // Thus stuff is basically copied from wiring_analog.c - if (start_conversion) - { - //Avoid doubled starts - start_conversion = false; - byte adcpin = (i2c_regs[0] & 0x7f); // Set the channel from the control reg, dropping the highest bit. -#if defined( CORE_ANALOG_FIRST ) - if ( adcpin >= CORE_ANALOG_FIRST ) adcpin -= CORE_ANALOG_FIRST; // allow for channel or pin numbers -#endif - // NOTE: These handy helpers (ADC_xxx) are only present in the tiny-core, for other cores you need to check their wiring_analog.c source. - ADC_SetInputChannel( (adc_ic_t)adcpin ); // we need to typecast - ADC_StartConversion(); - // Reset these variables - avg_count = 0; - avg_temp2 = 0; - } - - if ( bitRead(i2c_regs[0], 7) // We have conversion flag up - && !ADC_ConversionInProgress()) // But the conversion is complete - { - // So handle it - avg_temp1 = ADC_GetDataRegister(); - // Rolling average - if (avg_count) - { - avg_temp2 = (avg_temp2+avg_temp1)/2; - } - else - { - avg_temp2 = avg_temp1; - } - avg_count++; - if (avg_count >= i2c_regs[1]) - { - // All done, set the bytes to registers - cli(); - i2c_regs[2] = lowByte(avg_temp2); - i2c_regs[3] = highByte(avg_temp2); - sei(); - // And clear the conversion flag so the master knows we're ready - bitClear(i2c_regs[0], 7); - } - else - { - // Re-trigger conversion - ADC_StartConversion(); - } - } - -} |