diff --git a/bochs/cpu/extdb.cc b/bochs/cpu/extdb.cc
index 02c3e2f76..a4a91aae3 100644
--- a/bochs/cpu/extdb.cc
+++ b/bochs/cpu/extdb.cc
@@ -29,6 +29,7 @@ void bx_external_debugger(BX_CPU_C *cpu)
        break;
      }
 
+#if BX_SUPPORT_X86_64
      regs.rax = cpu->gen_reg[0].rrx;
      regs.rcx = cpu->gen_reg[1].rrx;
      regs.rdx = cpu->gen_reg[2].rrx;
@@ -46,6 +47,25 @@ void bx_external_debugger(BX_CPU_C *cpu)
      regs.r14 = cpu->gen_reg[14].rrx;
      regs.r15 = cpu->gen_reg[15].rrx;
      regs.rip = cpu->rip;
+#else
+     regs.rax = cpu->gen_reg[0].dword.erx;
+     regs.rcx = cpu->gen_reg[1].dword.erx;
+     regs.rdx = cpu->gen_reg[2].dword.erx;
+     regs.rbx = cpu->gen_reg[3].dword.erx;
+     regs.rsp = cpu->gen_reg[4].dword.erx;
+     regs.rbp = cpu->gen_reg[5].dword.erx;
+     regs.rsi = cpu->gen_reg[6].dword.erx;
+     regs.rdi = cpu->gen_reg[7].dword.erx;
+     regs.r8  = 0;
+     regs.r9  = 0;
+     regs.r10 = 0;
+     regs.r11 = 0;
+     regs.r12 = 0;
+     regs.r13 = 0;
+     regs.r14 = 0;
+     regs.r15 = 0;
+     regs.rip = cpu->dword.eip;
+#endif
      regs.rflags = cpu->read_eflags();
      regs.es = cpu->sregs[0].selector.value;
      regs.cs = cpu->sregs[1].selector.value;
@@ -68,9 +88,13 @@ void bx_external_debugger(BX_CPU_C *cpu)
      //regs.cr7 = cpu->cr7;
      regs.fsbase = cpu->sregs[BX_SEG_REG_FS].cache.u.segment.base;
      regs.gsbase = cpu->sregs[BX_SEG_REG_GS].cache.u.segment.base;
-     regs.efer = (BX_CPU_THIS_PTR msr.sce << 0)
+#if BX_SUPPORT_X86_64
+    regs.efer = (BX_CPU_THIS_PTR msr.sce << 0)
                | (BX_CPU_THIS_PTR msr.lme << 8)
                | (BX_CPU_THIS_PTR msr.lma << 10);
+#else
+    regs.efer = 0;
+#endif
 
      if (debug_loaded == 0) {
        HINSTANCE hdbg;