diff --git a/src/serial_util.c b/src/serial_util.c
index 090b648..a694a4c 100644
--- a/src/serial_util.c
+++ b/src/serial_util.c
@@ -23,6 +23,8 @@ static speed_t speed_from_string(char const *s) {
         return DEFAULT_SPEED;
     }
     switch (speed) {
+    case 0:
+        return B0;
     case 9600:
         return B9600;
     case 115200:
@@ -55,9 +57,12 @@ int serial_init(char const *serial_port, char const *speed) {
         fprintf(stderr, "Failed to get termios attrs.\n");
     }
 
-    if (cfsetspeed(&t_options, speed_from_string(speed)) < 0) {
-        fprintf(stderr, "Failed to set port speed.\n");
-        return 2;
+    speed_t s = speed_from_string(speed);
+    if (s != B0) {
+        if (cfsetspeed(&t_options, speed_from_string(speed)) < 0) {
+            fprintf(stderr, "Failed to set port speed.\n");
+            return 2;
+        }
     }
 
     t_options.c_lflag &= ~(ICANON | ECHO | ECHOE);