diff --git a/firmware/common/hackrf_core.c b/firmware/common/hackrf_core.c
index cd1c8005..792beec3 100644
--- a/firmware/common/hackrf_core.c
+++ b/firmware/common/hackrf_core.c
@@ -23,7 +23,6 @@
 
 #include "hackrf_core.h"
 #include "si5351c.h"
-#include "si5351c_drv.h"
 #include "max2837.h"
 #include "rffc5071.h"
 #include "sgpio.h"
@@ -36,6 +35,10 @@
 
 #define WAIT_CPU_CLOCK_INIT_DELAY   (10000)
 
+si5351c_driver_t clock_gen = {
+	.i2c_address = 0x60,
+};
+
 void delay(uint32_t duration)
 {
 	uint32_t i;
@@ -119,9 +122,9 @@ bool sample_rate_frac_set(uint32_t rate_num, uint32_t rate_denom)
 
 	/* Can we enable integer mode ? */
 	if (a & 0x1 || b)
-		si5351c_set_int_mode(0, 0);
+		si5351c_set_int_mode(&clock_gen, 0, 0);
 	else
-		si5351c_set_int_mode(0, 1);
+		si5351c_set_int_mode(&clock_gen, 0, 1);
 
 	/* Final MS values */
 	MSx_P1 = 128*a + (128 * b/c) - 512;
@@ -129,13 +132,13 @@ bool sample_rate_frac_set(uint32_t rate_num, uint32_t rate_denom)
 	MSx_P3 = c;
 
 	/* MS0/CLK0 is the source for the MAX5864/CPLD (CODEC_CLK). */
-	si5351c_configure_multisynth(0, MSx_P1, MSx_P2, MSx_P3, 1);
+	si5351c_configure_multisynth(&clock_gen, 0, MSx_P1, MSx_P2, MSx_P3, 1);
 
 	/* MS0/CLK1 is the source for the CPLD (CODEC_X2_CLK). */
-	si5351c_configure_multisynth(1, 0, 0, 0, 0);//p1 doesn't matter
+	si5351c_configure_multisynth(&clock_gen, 1, 0, 0, 0, 0);//p1 doesn't matter
 
 	/* MS0/CLK2 is the source for SGPIO (CODEC_X2_CLK) */
-	si5351c_configure_multisynth(2, 0, 0, 0, 0);//p1 doesn't matter
+	si5351c_configure_multisynth(&clock_gen, 2, 0, 0, 0, 0);//p1 doesn't matter
 
 	return true;
 }
@@ -175,13 +178,13 @@ bool sample_rate_set(const uint32_t sample_rate_hz) {
 	 * values are irrelevant. */
 	
 	/* MS0/CLK1 is the source for the MAX5864 codec. */
-	si5351c_configure_multisynth(1, 4608, 0, 1, r_div_sample);
+	si5351c_configure_multisynth(&clock_gen, 1, 4608, 0, 1, r_div_sample);
 
 	/* MS0/CLK2 is the source for the CPLD codec clock (same as CLK1). */
-	si5351c_configure_multisynth(2, 4608, 0, 1, r_div_sample);
+	si5351c_configure_multisynth(&clock_gen, 2, 4608, 0, 1, r_div_sample);
 
 	/* MS0/CLK3 is the source for the SGPIO clock. */
-	si5351c_configure_multisynth(3, 4608, 0, 1, r_div_sgpio);
+	si5351c_configure_multisynth(&clock_gen, 3, 4608, 0, 1, r_div_sgpio);
 	
 	return true;
 #endif
@@ -238,13 +241,13 @@ bool sample_rate_set(const uint32_t sample_rate_hz) {
 	}
 	
 	/* MS0/CLK0 is the source for the MAX5864/CPLD (CODEC_CLK). */
-	si5351c_configure_multisynth(0, p1, p2, p3, 1);
+	si5351c_configure_multisynth(&clock_gen, 0, p1, p2, p3, 1);
 
 	/* MS0/CLK1 is the source for the CPLD (CODEC_X2_CLK). */
-	si5351c_configure_multisynth(1, p1, 0, 1, 0);//p1 doesn't matter
+	si5351c_configure_multisynth(&clock_gen, 1, p1, 0, 1, 0);//p1 doesn't matter
 
 	/* MS0/CLK2 is the source for SGPIO (CODEC_X2_CLK) */
-	si5351c_configure_multisynth(2, p1, 0, 1, 0);//p1 doesn't matter
+	si5351c_configure_multisynth(&clock_gen, 2, p1, 0, 1, 0);//p1 doesn't matter
 
 	return true;
 #endif
@@ -267,13 +270,13 @@ void cpu_clock_init(void)
 
 	i2c0_init(15);
 
-	si5351c_disable_all_outputs();
-	si5351c_disable_oeb_pin_control();
-	si5351c_power_down_all_clocks();
-	si5351c_set_crystal_configuration();
-	si5351c_enable_xo_and_ms_fanout();
-	si5351c_configure_pll_sources();
-	si5351c_configure_pll_multisynth();
+	si5351c_disable_all_outputs(&clock_gen);
+	si5351c_disable_oeb_pin_control(&clock_gen);
+	si5351c_power_down_all_clocks(&clock_gen);
+	si5351c_set_crystal_configuration(&clock_gen);
+	si5351c_enable_xo_and_ms_fanout(&clock_gen);
+	si5351c_configure_pll_sources(&clock_gen);
+	si5351c_configure_pll_multisynth(&clock_gen);
 
 #ifdef JELLYBEAN
 	/*
@@ -289,13 +292,13 @@ void cpu_clock_init(void)
 	 */
 
 	/* MS0/CLK0 is the source for the MAX2837 clock input. */
-	si5351c_configure_multisynth(0, 2048, 0, 1, 0); /* 40MHz */
+	si5351c_configure_multisynth(&clock_gen, 0, 2048, 0, 1, 0); /* 40MHz */
 
 	/* MS4/CLK4 is the source for the LPC43xx microcontroller. */
-	si5351c_configure_multisynth(4, 8021, 0, 3, 0); /* 12MHz */
+	si5351c_configure_multisynth(&clock_gen, 4, 8021, 0, 3, 0); /* 12MHz */
 
 	/* MS5/CLK5 is the source for the RFFC5071 mixer. */
-	si5351c_configure_multisynth(5, 1536, 0, 1, 0); /* 50MHz */
+	si5351c_configure_multisynth(&clock_gen, 5, 1536, 0, 1, 0); /* 50MHz */
 #endif
 
 #if (defined JAWBREAKER || defined HACKRF_ONE)
@@ -312,28 +315,28 @@ void cpu_clock_init(void)
 	 */
 
 	/* MS3/CLK3 is the source for the external clock output. */
-	si5351c_configure_multisynth(3, 80*128-512, 0, 1, 0); /* 800/80 = 10MHz */
+	si5351c_configure_multisynth(&clock_gen, 3, 80*128-512, 0, 1, 0); /* 800/80 = 10MHz */
 
 	/* MS4/CLK4 is the source for the RFFC5071 mixer. */
-	si5351c_configure_multisynth(4, 16*128-512, 0, 1, 0); /* 800/16 = 50MHz */
+	si5351c_configure_multisynth(&clock_gen, 4, 16*128-512, 0, 1, 0); /* 800/16 = 50MHz */
  
  	/* MS5/CLK5 is the source for the MAX2837 clock input. */
-	si5351c_configure_multisynth(5, 20*128-512, 0, 1, 0); /* 800/20 = 40MHz */
+	si5351c_configure_multisynth(&clock_gen, 5, 20*128-512, 0, 1, 0); /* 800/20 = 40MHz */
 
 	/* MS6/CLK6 is unused. */
 	/* MS7/CLK7 is the source for the LPC43xx microcontroller. */
 	uint8_t ms7data[] = { 90, 255, 20, 0 };
-	si5351c_write(ms7data, sizeof(ms7data));
+	si5351c_write(&clock_gen, ms7data, sizeof(ms7data));
 #endif
 
 	/* Set to 10 MHz, the common rate between Jellybean and Jawbreaker. */
 	sample_rate_set(10000000);
 
-	si5351c_set_clock_source(PLL_SOURCE_XTAL);
+	si5351c_set_clock_source(&clock_gen, PLL_SOURCE_XTAL);
 	// soft reset
 	uint8_t resetdata[] = { 177, 0xac };
-	si5351c_write(resetdata, sizeof(resetdata));
-	si5351c_enable_clock_outputs();
+	si5351c_write(&clock_gen, resetdata, sizeof(resetdata));
+	si5351c_enable_clock_outputs(&clock_gen);
 
 	//FIXME disable I2C
 	/* Kick I2C0 down to 400kHz when we switch over to APB1 clock = 204MHz */
diff --git a/firmware/common/hackrf_core.h b/firmware/common/hackrf_core.h
index 8ce6c943..7ad1ad50 100644
--- a/firmware/common/hackrf_core.h
+++ b/firmware/common/hackrf_core.h
@@ -32,6 +32,8 @@ extern "C"
 #include <stdint.h>
 #include <stdbool.h>
 
+#include "si5351c_drv.h"
+
 /* hardware identification number */
 #define BOARD_ID_JELLYBEAN  0
 #define BOARD_ID_JAWBREAKER 1
@@ -350,6 +352,8 @@ typedef enum {
 
 void delay(uint32_t duration);
 
+extern si5351c_driver_t clock_gen;
+
 void cpu_clock_init(void);
 void cpu_clock_pll1_low_speed(void);
 void cpu_clock_pll1_max_speed(void);
diff --git a/firmware/common/si5351c.c b/firmware/common/si5351c.c
index 3be5041a..f6b4483a 100644
--- a/firmware/common/si5351c.c
+++ b/firmware/common/si5351c.c
@@ -27,21 +27,21 @@
 enum pll_sources active_clock_source;
 
 /* Disable all CLKx outputs. */
-void si5351c_disable_all_outputs()
+void si5351c_disable_all_outputs(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 3, 0xFF };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /* Turn off OEB pin control for all CLKx */
-void si5351c_disable_oeb_pin_control()
+void si5351c_disable_oeb_pin_control(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 9, 0xFF };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /* Power down all CLKx */
-void si5351c_power_down_all_clocks()
+void si5351c_power_down_all_clocks(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 16
 	, SI5351C_CLK_POWERDOWN
@@ -53,7 +53,7 @@ void si5351c_power_down_all_clocks()
 	, SI5351C_CLK_POWERDOWN | SI5351C_CLK_INT_MODE 
 	, SI5351C_CLK_POWERDOWN | SI5351C_CLK_INT_MODE
 	};
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /*
@@ -61,20 +61,20 @@ void si5351c_power_down_all_clocks()
  * Reads as 0xE4 on power-up
  * Set to 8pF based on crystal specs and HackRF One testing
  */
-void si5351c_set_crystal_configuration()
+void si5351c_set_crystal_configuration(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 183, 0x80 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /*
  * Register 187: Fanout Enable
  * Turn on XO and MultiSynth fanout only.
  */
-void si5351c_enable_xo_and_ms_fanout()
+void si5351c_enable_xo_and_ms_fanout(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 187, 0xD0 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /*
@@ -83,34 +83,35 @@ void si5351c_enable_xo_and_ms_fanout()
  * PLLA_SRC=0 (XTAL)
  * PLLB_SRC=1 (CLKIN)
  */
-void si5351c_configure_pll_sources(void)
+void si5351c_configure_pll_sources(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 15, 0x08 };
 
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 /* MultiSynth NA (PLLA) and NB (PLLB) */
-void si5351c_configure_pll_multisynth(void)
+void si5351c_configure_pll_multisynth(si5351c_driver_t* const drv)
 {
 	//init plla to (0x0e00+512)/128*25mhz xtal = 800mhz -> int mode
 	uint8_t data[] = { 26, 0x00, 0x01, 0x00, 0x0E, 0x00, 0x00, 0x00, 0x00 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 
 	/* 10 MHz input on CLKIN for PLLB */
 	data[0] = 34;
 	data[4] = 0x26;
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
-void si5351c_reset_pll(void)
+void si5351c_reset_pll(si5351c_driver_t* const drv)
 {
 	/* reset PLLA and PLLB */
 	uint8_t data[] = { 177, 0xA0 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
-void si5351c_configure_multisynth(const uint_fast8_t ms_number,
+void si5351c_configure_multisynth(si5351c_driver_t* const drv,
+		const uint_fast8_t ms_number,
 		const uint32_t p1, const uint32_t p2, const uint32_t p3,
     	const uint_fast8_t r_div)
 {
@@ -137,7 +138,7 @@ void si5351c_configure_multisynth(const uint_fast8_t ms_number,
 			(((p3 >> 16) & 0xF) << 4) | (((p2 >> 16) & 0xF) << 0),
 			(p2 >> 8) & 0xFF,
 			(p2 >> 0) & 0xFF };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 
 #ifdef JELLYBEAN
@@ -186,15 +187,15 @@ void si5351c_configure_multisynth(const uint_fast8_t ms_number,
  *   CLK5_SRC=3 (MS5 as input source)
  *   CLK5_IDRV=3 (8mA)
  */
-void si5351c_configure_clock_control()
+void si5351c_configure_clock_control(si5351c_driver_t* const drv)
 {
 	uint8_t data[] = { 16, 0x4F, 0x4B, 0x4B, 0x4B, 0x0F, 0x4F, 0xC0, 0xC0 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 #endif
 
 #if (defined JAWBREAKER || defined HACKRF_ONE)
-void si5351c_configure_clock_control(const enum pll_sources source)
+void si5351c_configure_clock_control(si5351c_driver_t* const drv, const enum pll_sources source)
 {
 	uint8_t pll;
 
@@ -215,54 +216,54 @@ void si5351c_configure_clock_control(const enum pll_sources source)
 	,SI5351C_CLK_POWERDOWN | SI5351C_CLK_INT_MODE /*not connected, but: plla int mode*/
 	,SI5351C_CLK_INT_MODE | SI5351C_CLK_PLL_SRC(pll) | SI5351C_CLK_SRC(SI5351C_CLK_SRC_MULTISYNTH_SELF) | SI5351C_CLK_IDRV(SI5351C_CLK_IDRV_8MA)
 	 };
-	si5351c_write(data, sizeof(data));
+	si5351c_write(drv, data, sizeof(data));
 }
 #endif
 
 /* Enable CLK outputs 0, 1, 2, 3, 4, 5, 7 only. */
- void si5351c_enable_clock_outputs()
+ void si5351c_enable_clock_outputs(si5351c_driver_t* const drv)
  {
 	uint8_t data[] = { 3, 0x40 };
- 	si5351c_write(data, sizeof(data));
+ 	si5351c_write(drv, data, sizeof(data));
  }
 
 
- void si5351c_set_int_mode(const uint_fast8_t ms_number, const uint_fast8_t on){
+ void si5351c_set_int_mode(si5351c_driver_t* const drv, const uint_fast8_t ms_number, const uint_fast8_t on){
   uint8_t data[] = {16, 0};
 
   if(ms_number < 8){
       data[0] = 16 + ms_number;
-      data[1] = si5351c_read_single(data[0]);
+      data[1] = si5351c_read_single(drv, data[0]);
 
       if(on)
           data[1] |= SI5351C_CLK_INT_MODE;
       else
           data[1] &= ~(SI5351C_CLK_INT_MODE);
 
-      si5351c_write(data, 2);
+      si5351c_write(drv, data, 2);
   }
 
  }
 
-void si5351c_set_clock_source(const enum pll_sources source)
+void si5351c_set_clock_source(si5351c_driver_t* const drv, const enum pll_sources source)
 {
-	si5351c_configure_clock_control(source);
+	si5351c_configure_clock_control(drv, source);
 	active_clock_source = source;
 }
 
-void si5351c_activate_best_clock_source(void)
+void si5351c_activate_best_clock_source(si5351c_driver_t* const drv)
 {
-	uint8_t device_status = si5351c_read_single(0);
+	uint8_t device_status = si5351c_read_single(drv, 0);
 
 	if (device_status & SI5351C_LOS) {
 		/* CLKIN not detected */
 		if (active_clock_source == PLL_SOURCE_CLKIN) {
-			si5351c_set_clock_source(PLL_SOURCE_XTAL);
+			si5351c_set_clock_source(drv, PLL_SOURCE_XTAL);
 		}
 	} else {
 		/* CLKIN detected */
 		if (active_clock_source == PLL_SOURCE_XTAL) {
-			si5351c_set_clock_source(PLL_SOURCE_CLKIN);
+			si5351c_set_clock_source(drv, PLL_SOURCE_CLKIN);
 		}
 	}
 }
diff --git a/firmware/common/si5351c.h b/firmware/common/si5351c.h
index fcc2d2b8..7151f990 100644
--- a/firmware/common/si5351c.h
+++ b/firmware/common/si5351c.h
@@ -30,6 +30,8 @@ extern "C"
 
 #include <stdint.h>
 
+#include "si5351c_drv.h"
+
 #define SI_INTDIV(x)  (x*128-512)
 
 #define SI5351C_CLK_POWERDOWN	(1<<7)
@@ -61,22 +63,23 @@ enum pll_sources {
 	PLL_SOURCE_CLKIN = 1,
 };
 
-void si5351c_disable_all_outputs();
-void si5351c_disable_oeb_pin_control();
-void si5351c_power_down_all_clocks();
-void si5351c_set_crystal_configuration();
-void si5351c_enable_xo_and_ms_fanout();
-void si5351c_configure_pll_sources(void);
-void si5351c_configure_pll_multisynth(void);
-void si5351c_reset_pll(void);
-void si5351c_configure_multisynth(const uint_fast8_t ms_number,
+void si5351c_disable_all_outputs(si5351c_driver_t* const drv);
+void si5351c_disable_oeb_pin_control(si5351c_driver_t* const drv);
+void si5351c_power_down_all_clocks(si5351c_driver_t* const drv);
+void si5351c_set_crystal_configuration(si5351c_driver_t* const drv);
+void si5351c_enable_xo_and_ms_fanout(si5351c_driver_t* const drv);
+void si5351c_configure_pll_sources(si5351c_driver_t* const drv);
+void si5351c_configure_pll_multisynth(si5351c_driver_t* const drv);
+void si5351c_reset_pll(si5351c_driver_t* const drv);
+void si5351c_configure_multisynth(si5351c_driver_t* const drv,
+		const uint_fast8_t ms_number,
     	const uint32_t p1, const uint32_t p2, const uint32_t p3,
     	const uint_fast8_t r_div);
-void si5351c_configure_clock_control(const enum pll_sources source);
-void si5351c_enable_clock_outputs();
-void si5351c_set_int_mode(const uint_fast8_t ms_number, const uint_fast8_t on);
-void si5351c_set_clock_source(const enum pll_sources source);
-void si5351c_activate_best_clock_source(void);
+void si5351c_configure_clock_control(si5351c_driver_t* const drv, const enum pll_sources source);
+void si5351c_enable_clock_outputs(si5351c_driver_t* const drv);
+void si5351c_set_int_mode(si5351c_driver_t* const drv, const uint_fast8_t ms_number, const uint_fast8_t on);
+void si5351c_set_clock_source(si5351c_driver_t* const drv, const enum pll_sources source);
+void si5351c_activate_best_clock_source(si5351c_driver_t* const drv);
 
 #ifdef __cplusplus
 }
diff --git a/firmware/common/si5351c_drv.c b/firmware/common/si5351c_drv.c
index e63912c1..4cb58cd6 100644
--- a/firmware/common/si5351c_drv.c
+++ b/firmware/common/si5351c_drv.c
@@ -29,28 +29,28 @@
 /* FIXME return i2c0 status from each function */
 
 /* write to single register */
-void si5351c_write_single(uint8_t reg, uint8_t val)
+void si5351c_write_single(si5351c_driver_t* const drv, uint8_t reg, uint8_t val)
 {
 	i2c0_tx_start();
-	i2c0_tx_byte(SI5351C_I2C_ADDR | I2C_WRITE);
+	i2c0_tx_byte((drv->i2c_address << 1) | I2C_WRITE);
 	i2c0_tx_byte(reg);
 	i2c0_tx_byte(val);
 	i2c0_stop();
 }
 
 /* read single register */
-uint8_t si5351c_read_single(uint8_t reg)
+uint8_t si5351c_read_single(si5351c_driver_t* const drv, uint8_t reg)
 {
 	uint8_t val;
 
 	/* set register address with write */
 	i2c0_tx_start();
-	i2c0_tx_byte(SI5351C_I2C_ADDR | I2C_WRITE);
+	i2c0_tx_byte((drv->i2c_address << 1) | I2C_WRITE);
 	i2c0_tx_byte(reg);
 
 	/* read the value */
 	i2c0_tx_start();
-	i2c0_tx_byte(SI5351C_I2C_ADDR | I2C_READ);
+	i2c0_tx_byte((drv->i2c_address << 1) | I2C_READ);
 	val = i2c0_rx_byte();
 	i2c0_stop();
 
@@ -61,12 +61,12 @@ uint8_t si5351c_read_single(uint8_t reg)
  * Write to one or more contiguous registers. data[0] should be the first
  * register number, one or more values follow.
  */
-void si5351c_write(uint8_t* const data, const uint_fast8_t data_count)
+void si5351c_write(si5351c_driver_t* const drv, uint8_t* const data, const uint_fast8_t data_count)
 {
 	uint_fast8_t i;
 
 	i2c0_tx_start();
-	i2c0_tx_byte(SI5351C_I2C_ADDR | I2C_WRITE);
+	i2c0_tx_byte((drv->i2c_address << 1) | I2C_WRITE);
 	
 	for (i = 0; i < data_count; i++)
 		i2c0_tx_byte(data[i]);
diff --git a/firmware/common/si5351c_drv.h b/firmware/common/si5351c_drv.h
index 501b221e..61c6f374 100644
--- a/firmware/common/si5351c_drv.h
+++ b/firmware/common/si5351c_drv.h
@@ -30,9 +30,13 @@ extern "C"
 
 #include <stdint.h>
 
-void si5351c_write_single(uint8_t reg, uint8_t val);
-uint8_t si5351c_read_single(uint8_t reg);
-void si5351c_write(uint8_t* const data, const uint_fast8_t data_count);
+typedef struct {
+	uint8_t i2c_address;
+} si5351c_driver_t;
+
+void si5351c_write_single(si5351c_driver_t* const drv, uint8_t reg, uint8_t val);
+uint8_t si5351c_read_single(si5351c_driver_t* const drv, uint8_t reg);
+void si5351c_write(si5351c_driver_t* const drv, uint8_t* const data, const uint_fast8_t data_count);
 
 #ifdef __cplusplus
 }
diff --git a/firmware/hackrf_usb/hackrf_usb.c b/firmware/hackrf_usb/hackrf_usb.c
index 42fc4482..0ed260c5 100644
--- a/firmware/hackrf_usb/hackrf_usb.c
+++ b/firmware/hackrf_usb/hackrf_usb.c
@@ -75,7 +75,7 @@ void set_transceiver_mode(const transceiver_mode_t new_transceiver_mode) {
 	}
 
 	if( _transceiver_mode != TRANSCEIVER_MODE_OFF ) {
-		si5351c_activate_best_clock_source();
+		si5351c_activate_best_clock_source(&clock_gen);
 		baseband_streaming_enable();
 	}
 }
diff --git a/firmware/hackrf_usb/usb_api_register.c b/firmware/hackrf_usb/usb_api_register.c
index 9478e7c1..35b9e012 100644
--- a/firmware/hackrf_usb/usb_api_register.c
+++ b/firmware/hackrf_usb/usb_api_register.c
@@ -22,9 +22,9 @@
 
 #include "usb_api_register.h"
 
+#include <hackrf_core.h>
 #include <usb_queue.h>
 #include <max2837.h>
-#include <si5351c_drv.h>
 #include <rffc5071.h>
 
 #include <stddef.h>
@@ -75,7 +75,7 @@ usb_request_status_t usb_vendor_request_write_si5351c(
 	if( stage == USB_TRANSFER_STAGE_SETUP ) {
 		if( endpoint->setup.index < 256 ) {
 			if( endpoint->setup.value < 256 ) {
-				si5351c_write_single(endpoint->setup.index, endpoint->setup.value);
+				si5351c_write_single(&clock_gen, endpoint->setup.index, endpoint->setup.value);
 				usb_transfer_schedule_ack(endpoint->in);
 				return USB_REQUEST_STATUS_OK;
 			}
@@ -92,7 +92,7 @@ usb_request_status_t usb_vendor_request_read_si5351c(
 ) {
 	if( stage == USB_TRANSFER_STAGE_SETUP ) {
 		if( endpoint->setup.index < 256 ) {
-			const uint8_t value = si5351c_read_single(endpoint->setup.index);
+			const uint8_t value = si5351c_read_single(&clock_gen, endpoint->setup.index);
 			endpoint->buffer[0] = value;
 			usb_transfer_schedule_block(endpoint->in, &endpoint->buffer, 1,
 						    NULL, NULL);