diff --git a/src/devices/machine/68340tmu.cpp b/src/devices/machine/68340tmu.cpp
index d66f1f2387c..96157eafc53 100644
--- a/src/devices/machine/68340tmu.cpp
+++ b/src/devices/machine/68340tmu.cpp
@@ -156,7 +156,7 @@ void mc68340_timer_module_device::write(offs_t offset, uint16_t data, uint16_t m
 				   "Period Measurement - not implemented",
 				   "Event Count - not implemented",
 				   "Timer Bypass (Simple Test Method) - not implemented"
-			 }}[data & REG_CR_MODE_MASK]);
+			 }}[(data & REG_CR_MODE_MASK) >> 2]);
 
 		LOGTIMER("- OC: %s mode\n", std::array<char const *, 4>{{"Disabled", "Toggle", "Zero", "One"}}[data & REG_CR_OC_MASK]);