diff --git a/include/ps2000_internal.h b/include/ps2000_internal.h
index 2fdc609..6c4651a 100644
--- a/include/ps2000_internal.h
+++ b/include/ps2000_internal.h
@@ -526,6 +526,10 @@ int             _ps2000_ops_check_device_state(ps2000_context_t *ctx);
 void            _ps2000_ops_update_device_state(ps2000_context_t *ctx);
 int             _ps2000_ops_siggen_default_init(ps2000_context_t *ctx);
 int             _ps2000_ops_check_channel(ps2000_context_t *ctx);
+/* FIX #16: Extended validation with frequency check */
+int             _ps2000_ops_validate_siggen_freq(ps2000_context_t *ctx,
+                                                 double freq_normalized,
+                                                 uint32_t awg_samples);
 
 /* --- USB Transport (_ps2000_usb_*) --- */
 ps2000_status_t _ps2000_usb_open_device(ps2000_context_t *ctx, uint32_t serial);
@@ -539,8 +543,9 @@ ps2000_status_t _ps2000_usb_bulk_transfer(ps2000_context_t *ctx, uint8_t ep,
 
 /* --- HW / IO commands (_ps2000_hw_*) --- */
 ps2000_status_t _ps2000_hw_init_sequence(ps2000_context_t *ctx);
-ps2000_status_t _ps2000_hw_write_reg(ps2000_context_t *ctx, uint8_t reg, uint16_t val);
-ps2000_status_t _ps2000_hw_read_reg(ps2000_context_t *ctx, uint8_t reg, uint16_t *val);
+/* FIX #13: reg parameter changed to uint16_t */
+ps2000_status_t _ps2000_hw_write_reg(ps2000_context_t *ctx, uint16_t reg, uint16_t val);
+ps2000_status_t _ps2000_hw_read_reg(ps2000_context_t *ctx, uint16_t reg, uint16_t *val);
 ps2000_status_t _ps2000_hw_load_fpga(ps2000_context_t *ctx,
                                      const uint8_t *bitstream, uint32_t len);
 ps2000_status_t _ps2000_hw_adc_spi_write(ps2000_context_t *ctx,
@@ -548,6 +553,10 @@ ps2000_status_t _ps2000_hw_adc_spi_write(ps2000_context_t *ctx,
 ps2000_status_t _ps2000_hw_io_cmd(ps2000_context_t *ctx, ps2000_io_cmd_t cmd,
                                   uint16_t addr, uint16_t value);
 void            _ps2000_hw_cleanup(ps2000_context_t *ctx);
+/* FIX #15: PreLaunch */
+ps2000_status_t _ps2000_hw_prelaunch(void);
+/* FIX #15: Apply fix */
+int             _ps2000_hw_apply_fix(uint32_t magic, uint16_t version);
 
 /* --- Init table parser (_ps2000_init_tbl_*) --- */
 ps2000_status_t _ps2000_init_tbl_execute(ps2000_context_t *ctx,