diff --git a/pyocd/coresight/dap.py b/pyocd/coresight/dap.py
index d69fed2ab..a6665c1a7 100644
--- a/pyocd/coresight/dap.py
+++ b/pyocd/coresight/dap.py
@@ -69,7 +69,6 @@
 
 BASEPTR0_VALID_MASK = 0x00000001
 BASEPTR0_PTR_MASK = 0xfffff000
-BASEPTR0_PTR_SHIFT = 12
 
 ABORT_DAPABORT = 0x00000001
 ABORT_STKCMPCLR = 0x00000002
@@ -498,7 +497,7 @@ def _check_version(self) -> None:
             baseptr0 = self.read_reg(DP_BASEPTR0)
             valid = (baseptr0 & BASEPTR0_VALID_MASK) != 0
             if valid:
-                base = (baseptr0 & BASEPTR0_PTR_MASK) >> BASEPTR0_PTR_SHIFT
+                base = baseptr0 & BASEPTR0_PTR_MASK
                 if self._addr_size > 32:
                     baseptr1 = self.read_reg(DP_BASEPTR1)
                     base |= baseptr1 << 32