diff --git a/devices/common/pci/pcibase.cpp b/devices/common/pci/pcibase.cpp
index 08f24b7..71d1110 100644
--- a/devices/common/pci/pcibase.cpp
+++ b/devices/common/pci/pcibase.cpp
@@ -48,7 +48,7 @@ PCIBase::PCIBase(std::string name, PCIHeaderType hdr_type, int num_bars)
             FIXME: should register or unregister BAR mmio regions if (cmd & 2) changes.
             Or the mmio regions should be enabled/disabled.
         */
-        this->command = cmd;
+        this->command = cmd & this->command_cfg;
     };
     this->pci_wr_bist       = [](uint8_t  val) {};
     this->pci_wr_lat_timer  = [this](uint8_t val) { this->lat_timer = val; };
diff --git a/devices/common/pci/pcibase.h b/devices/common/pci/pcibase.h
index 420671a..d26f292 100644
--- a/devices/common/pci/pcibase.h
+++ b/devices/common/pci/pcibase.h
@@ -171,6 +171,9 @@ protected:
     uint32_t    exp_rom_size = 0;    // expansion ROM size in bytes
 
     std::unique_ptr<uint8_t[]> exp_rom_data;
+
+    // 0 = not writable; 1 = bit is enabled in command register
+    uint16_t    command_cfg = 0xffff - (1<<3) - (1<<7); // disable: special cycles and stepping
 };
 
 inline uint32_t pci_cfg_log(uint32_t value, AccessDetails &details) {