diff --git a/src/devices/cpu/clipper/clipper.cpp b/src/devices/cpu/clipper/clipper.cpp
index ee77197e967..5c05703a2af 100644
--- a/src/devices/cpu/clipper/clipper.cpp
+++ b/src/devices/cpu/clipper/clipper.cpp
@@ -1864,17 +1864,27 @@ void clipper_c400_device::execute_instruction()
 
 	case 0x4a:
 	case 0x4b:
-		// cdb: call with delayed branch?
+		// cdb: compare and delayed branch?
 		// emulate.h: "cdb is special because it does not support all addressing modes", 2-3 parcels
 		fatalerror("cdb pc 0x%08x\n", m_info.pc);
 	case 0x4c:
 	case 0x4d:
-		// cdbeq: call with delayed branch if equal?
-		fatalerror("cdbeq pc 0x%08x\n", m_info.pc);
+		// cdbeq: compare and delayed branch if equal?
+		if (m_r[R2] == 0)
+		{
+			m_psw |= DSP_SETUP;
+			m_db_pc = m_info.address;
+		}
+		break;
 	case 0x4e:
 	case 0x4f:
-		// cdbne: call with delayed branch if not equal?
-		fatalerror("cdbne pc 0x%08x\n", m_info.pc);
+		// cdbne: compare and delayed branch if not equal?
+		if (m_r[R2] != 0)
+		{
+			m_psw |= DSP_SETUP;
+			m_db_pc = m_info.address;
+		}
+		break;
 	case 0x50:
 	case 0x51:
 		// db*: delayed branch on condition