diff --git a/isotprecv.c b/isotprecv.c
index 9e37c86..acd6de6 100644
--- a/isotprecv.c
+++ b/isotprecv.c
@@ -71,6 +71,7 @@ void print_usage(char *prg)
 	fprintf(stderr, "         -P <mode>    (check padding in SF/CF. (l)ength (c)ontent (a)ll)\n");
 	fprintf(stderr, "         -b <bs>      (blocksize. 0 = off)\n");
 	fprintf(stderr, "         -m <val>     (STmin in ms/ns. See spec.)\n");
+	fprintf(stderr, "         -f <time ns> (force rx stmin value in nanosecs)\n");
 	fprintf(stderr, "         -w <num>     (max. wait frame transmissions.)\n");
 	fprintf(stderr, "         -l           (loop: do not exit after pdu receiption.)\n");
 	fprintf(stderr, "\nCAN IDs and addresses are given and expected in hexadecimal values.\n");
@@ -87,6 +88,7 @@ int main(int argc, char **argv)
     static struct can_isotp_fc_options fcopts;
     int opt, i;
     extern int optind, opterr, optopt;
+    __u32 force_rx_stmin = 0;
     int loop = 0;
 
     unsigned char msg[4096];
@@ -94,7 +96,7 @@ int main(int argc, char **argv)
 
     addr.can_addr.tp.tx_id = addr.can_addr.tp.rx_id = NO_CAN_ID;
 
-    while ((opt = getopt(argc, argv, "s:d:x:p:P:b:m:w:l?")) != -1) {
+    while ((opt = getopt(argc, argv, "s:d:x:p:P:b:m:w:f:l?")) != -1) {
 	    switch (opt) {
 	    case 's':
 		    addr.can_addr.tp.tx_id = strtoul(optarg, (char **)NULL, 16);
@@ -144,6 +146,11 @@ int main(int argc, char **argv)
 		    fcopts.wftmax = strtoul(optarg, (char **)NULL, 16) & 0xFF;
 		    break;
 
+	    case 'f':
+		    opts.flags |= CAN_ISOTP_FORCE_RXSTMIN;
+		    force_rx_stmin = strtoul(optarg, (char **)NULL, 10);
+		    break;
+
 	    case 'l':
 		    loop = 1;
 		    break;
@@ -176,6 +183,9 @@ int main(int argc, char **argv)
     setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_OPTS, &opts, sizeof(opts));
     setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_RECV_FC, &fcopts, sizeof(fcopts));
 
+    if (opts.flags & CAN_ISOTP_FORCE_RXSTMIN)
+	    setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_RX_STMIN, &force_rx_stmin, sizeof(force_rx_stmin));
+
     addr.can_family = AF_CAN;
     strcpy(ifr.ifr_name, argv[optind]);
     ioctl(s, SIOCGIFINDEX, &ifr);
diff --git a/isotpsend.c b/isotpsend.c
index bcaa35b..015dca6 100644
--- a/isotpsend.c
+++ b/isotpsend.c
@@ -69,7 +69,8 @@ void print_usage(char *prg)
 	fprintf(stderr, "         -x <addr>    (extended addressing mode. Use 'any' for all addresses)\n");
 	fprintf(stderr, "         -p <byte>    (set and enable padding byte)\n");
 	fprintf(stderr, "         -P <mode>    (check padding in FC. (l)ength (c)ontent (a)ll)\n");
-	fprintf(stderr, "         -t <time ns> (transmit time in nanosecs)\n");
+	fprintf(stderr, "         -t <time ns> (frame transmit time (N_As) in nanosecs)\n");
+	fprintf(stderr, "         -f <time ns> (ignore FC and force local tx stmin value in nanosecs)\n");
 	fprintf(stderr, "\nCAN IDs and addresses are given and expected in hexadecimal values.\n");
 	fprintf(stderr, "The pdu data is expected on STDIN in space separated ASCII hex values.\n");
 	fprintf(stderr, "\n");
@@ -83,12 +84,13 @@ int main(int argc, char **argv)
     static struct can_isotp_options opts;
     int opt;
     extern int optind, opterr, optopt;
+    __u32 force_tx_stmin = 0;
     unsigned char buf[4096];
     int buflen = 0;
 
     addr.can_addr.tp.tx_id = addr.can_addr.tp.rx_id = NO_CAN_ID;
 
-    while ((opt = getopt(argc, argv, "s:d:x:p:P:t:?")) != -1) {
+    while ((opt = getopt(argc, argv, "s:d:x:p:P:t:f:?")) != -1) {
 	    switch (opt) {
 	    case 's':
 		    addr.can_addr.tp.tx_id = strtoul(optarg, (char **)NULL, 16);
@@ -130,6 +132,11 @@ int main(int argc, char **argv)
 		    opts.frame_txtime = strtoul(optarg, (char **)NULL, 10);
 		    break;
 
+	    case 'f':
+		    opts.flags |= CAN_ISOTP_FORCE_TXSTMIN;
+		    force_tx_stmin = strtoul(optarg, (char **)NULL, 10);
+		    break;
+
 	    case '?':
 		    print_usage(basename(argv[0]));
 		    exit(0);
@@ -157,6 +164,9 @@ int main(int argc, char **argv)
 
     setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_OPTS, &opts, sizeof(opts));
 
+    if (opts.flags & CAN_ISOTP_FORCE_TXSTMIN)
+	    setsockopt(s, SOL_CAN_ISOTP, CAN_ISOTP_TX_STMIN, &force_tx_stmin, sizeof(force_tx_stmin));
+
     addr.can_family = AF_CAN;
     strcpy(ifr.ifr_name, argv[optind]);
     ioctl(s, SIOCGIFINDEX, &ifr);