diff --git a/src/mame/drivers/microterm_f8.cpp b/src/mame/drivers/microterm_f8.cpp
index 99f90a85a26..c91f19a5e89 100644
--- a/src/mame/drivers/microterm_f8.cpp
+++ b/src/mame/drivers/microterm_f8.cpp
@@ -114,6 +114,8 @@ u32 microterm_f8_state::screen_update(screen_device &screen, bitmap_rgb32 &bitma
 			u16 ch = m_vram[rowbase + (x / 9)];
 			u8 chdata = m_chargen[(line << 7) | (ch & 0x7f)];
 			bool dot = (!BIT(ch, 8) && allow_underline) || BIT(chdata, 8 - (x % 9));
+			if (BIT(ch, 7) == BIT(ch, 9))
+				dot = !dot;
 			bitmap.pix32(y, x) = dot ? rgb_t::white() : rgb_t::black();
 		}