Index: share/mk/src.opts.mk
===================================================================
--- share/mk/src.opts.mk
+++ share/mk/src.opts.mk
@@ -202,6 +202,7 @@
 __DEFAULT_NO_OPTIONS = \
     BEARSSL \
     BHYVE_SNAPSHOT \
+    BOOT0_RESET_TERM \
     CLANG_EXTRAS \
     CLANG_FORMAT \
     DTRACE_TESTS \
Index: stand/i386/boot0/Makefile
===================================================================
--- stand/i386/boot0/Makefile
+++ stand/i386/boot0/Makefile
@@ -14,6 +14,7 @@
 #	-DCHECK_DRIVE	enable checking drive number
 #	-DONLY_F_KEYS	accept only Fx keys in console
 #	-DTEST		print drive number on entry
+#	-DRESET_TERM    send terminal reset command before first output
 #
 OPTS ?= -DVOLUME_SERIAL -DPXE
 CFLAGS += ${OPTS}
Index: stand/i386/boot0/boot0.S
===================================================================
--- stand/i386/boot0/boot0.S
+++ stand/i386/boot0/boot0.S
@@ -216,6 +216,14 @@
 		callw bioscom
 #endif
 
+#if defined(SIO) && defined(RESET_TERM)
+	/*
+	 * ANSI / VT100 command to reset all terminal attributes
+	 */
+		movw $resetterm,%si		# Reset
+		callw putstr			#  terminal
+#endif
+
 	/*
 	 * If the 'setdrv' flag is set in the boot sector, use the drive
 	 * number from the boot sector at 'setdrv_num'.
@@ -584,6 +592,14 @@
 		popw %si			# Restore
 		retw				# To caller
 
+#if defined(SIO) && defined(RESET_TERM)
+	/*
+	 * Reset terminal ANSI/VT100 sequence
+	 */
+resetterm:
+		.byte 0x1b; .byte 'c'|0x80
+#endif
+
 /*
  * Various menu strings. 'item' goes after 'prompt' to save space.
  * Also use shorter versions to make room for the PXE/INT18 code.
Index: stand/i386/boot0sio/Makefile
===================================================================
--- stand/i386/boot0sio/Makefile
+++ stand/i386/boot0sio/Makefile
@@ -2,7 +2,13 @@
 
 .PATH: ${.CURDIR}/../boot0
 
+.include <src.opts.mk>
+
 PROGNAME=	boot0sio
 CFLAGS+=	-DSIO
 
+.if ${MK_BOOT0_RESET_TERM} != "no"
+OPTS ?=		-DRESET_TERM -DSAVE_MEMORY -DPXE
+.endif
+
 .include "${.CURDIR}/../boot0/Makefile"
Index: tools/build/options/WITH_BOOT0_RESET_TERM
===================================================================
--- /dev/null
+++ tools/build/options/WITH_BOOT0_RESET_TERM
@@ -0,0 +1,5 @@
+.\" $FreeBSD$
+Set to build boot0sio to send default VT-100 reset command <ESC>c before first
+output. 
+This option is not compatible with PXE and VOLUME_SERIAL options, due to space
+constraints.