--- a/test-fsk/rtp_tx.c	Mon Mar 04 21:22:27 2024 -0800
+++ b/test-fsk/rtp_tx.c	Mon Mar 04 22:08:19 2024 -0800
@@ -12,19 +12,23 @@
 #include <string.h>
 #include <strings.h>
 #include <unistd.h>
+#include <spandsp.h>
 #include "../include/tmgw_const.h"
 #include "../include/rtp_defs.h"
+#include "../include/pstn_defs.h"
 #include "../libutil/osmo_bits.h"
 
 extern struct sockaddr_in rtp_local_addr, rtp_remote_addr;
 extern int rtp_udp_fd, rtcp_udp_fd, pcma_selected;
 extern struct timeval cur_event_time;
+extern int fsk_mode_tx;
 
 static uint32_t rtp_ssrc;
 static uint32_t rtp_out_ts;
 static uint16_t rtp_out_seq;
 
-static uint8_t pcm_fill_octet;
+static fsk_tx_state_t *fsk_tx_state;
+static g711_state_t *g711_enc_state;
 
 void
 assign_rtpout_ssrc()
@@ -32,13 +36,26 @@
 	rtp_ssrc = cur_event_time.tv_sec ^ cur_event_time.tv_usec ^ getpid();
 }
 
+static int
+supply_bit()
+{
+	return 1;
+}
+
 void
-init_pcm_fill_octet()
+init_pcm_tx()
 {
-	if (pcma_selected)
-		pcm_fill_octet = 0xD5;
-	else
-		pcm_fill_octet = 0xFF;
+	fsk_tx_state = fsk_tx_init(NULL, &preset_fsk_specs[fsk_mode_tx],
+				   supply_bit, NULL);
+	if (!fsk_tx_state) {
+		fprintf(stderr, "error: fsk_tx_init() failed!\n");
+		exit(1);
+	}
+	g711_enc_state = g711_init(NULL, pcma_selected ? G711_ALAW : G711_ULAW);
+	if (!g711_enc_state) {
+		fprintf(stderr, "error: g711_init() failed!\n");
+		exit(1);
+	}
 }
 
 void
@@ -46,22 +63,17 @@
 {
 	struct rtp_packet pkt;
 	socklen_t addrlen;
+	int16_t linear[FRAME_20MS];
 
 	pkt.v_p_x_cc = 0x80;
 	pkt.m_pt = pcma_selected ? PSTN_CODEC_PCMA : PSTN_CODEC_PCMU;
 	pkt.seq = htons(rtp_out_seq++);
 	pkt.tstamp = htonl(rtp_out_ts);
-	rtp_out_ts += 160;
+	rtp_out_ts += FRAME_20MS;
 	pkt.ssrc = rtp_ssrc;
-	memset(pkt.payload, pcm_fill_octet, RTP_MAX_PAYLOAD);
+	fsk_tx(fsk_tx_state, linear, FRAME_20MS);
+	g711_encode(g711_enc_state, pkt.payload, linear, FRAME_20MS);
 	addrlen = sizeof(struct sockaddr_in);
 	sendto(rtp_udp_fd, &pkt, RTP_PACKET_SIZE_PSTN, 0,
 		(struct sockaddr *) &rtp_remote_addr, addrlen);
 }
-
-void
-set_pcm_fill_octet(oct)
-	unsigned oct;
-{
-	pcm_fill_octet = oct;
-}