32 lines
843 B
C
32 lines
843 B
C
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#include "i2c.h"
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void init_i2c(void) {
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// Initialize the control A register
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TWI0.CTRLA = TWI_INPUTLVL_I2C_gc // I2C voltage transition level
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| TWI_SDASETUP_4CYC_gc // Four clock cycles setup time
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| TWI_SDAHOLD_50NS_gc // 50ns SDA hold time
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| TWI_FMPEN_OFF_gc // Standard SPI timing
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;
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// The device's slave address
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TWI0.SADDR = 0x42;
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// Enable acting as a slave
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TWI0.SCTRLA = TWI_DIEN_bm // Enable data interrupt
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| TWI_PIEN_bm // Enable stop flag interrupt
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| TWI_SMEN_bm // Enable smart mode
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| TWI_ENABLE_bm // Enable acting as a slave
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;
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}
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// TODO: Figure out which interrupt does what
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// Interrupt vector
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ISR(TWI0_TWIS_vect) {
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asm('nop');
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}
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// Interrupt vector
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ISR(TWI0_TWIM_vect) {
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asm('nop');
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}
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