--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/target-utils/simtest/poll.c	Sat Feb 09 07:55:50 2019 +0000
@@ -0,0 +1,49 @@
+#include <sys/types.h>
+#include <strings.h>
+#include "types.h"
+#include "simregs.h"
+
+extern int serial_in_poll();
+
+int enable_poll;
+
+void
+poll_sim_rx()
+{
+	u32 drx;
+
+	if (SIMREGS.stat & 3)
+		return;
+	drx = SIMREGS.drx & 0xFF;
+	printf("%02X ", drx);
+}
+
+int
+mygetchar()
+{
+	register int c;
+
+	do {
+		if (enable_poll)
+			poll_sim_rx();
+		c = serial_in_poll();
+	}
+	while (c < 0);
+	return c;
+}
+
+void
+cmd_poll(argbulk)
+	char *argbulk;
+{
+	char *argv[2];
+
+	if (parse_args(argbulk, 1, 1, argv, 0) < 0)
+		return;
+	if (!strcmp(argv[0], "on"))
+		enable_poll = 1;
+	else if (!strcmp(argv[0], "off"))
+		enable_poll = 0;
+	else
+		printf("ERROR: \"on\" or \"off\" argument expected\n");
+}