--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/autocal/txlevels.c	Sat Jul 15 22:48:29 2017 +0000
@@ -0,0 +1,33 @@
+/*
+ * The calibration of Tx power levels is implemented here.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <rvinterf/l1tm.h>
+#include <rvinterf/exitcodes.h>
+#include "txband.h"
+
+extern double tx_power_meas();
+extern vout_t dbm_to_vout();
+
+extern struct txcal_band *txcal_band;
+extern struct tx_basis_point tx_basis[MAX_BASIS_POINTS];
+extern unsigned num_basis_points;
+extern struct tx_level tx_levels[MAX_TX_LEVELS];
+
+unsigned
+find_apc_for_target(target_dbm)
+	double target_dbm;
+{
+	vout_t target_vout;
+	unsigned n;
+	int apc_delta;
+
+	target_vout = dbm_to_vout(target_dbm);
+	for (n = 0; n < num_basis_points - 1; n++)
+		if (target_vout < tx_basis[n+1].vout)
+			break;
+	apc_delta = (target_vout - tx_basis[n].vout) / tx_basis[n].slope;
+	return tx_basis[n].apc + apc_delta;
+}