Revert "keil c 51"

This reverts commit 74f4f12a1e60376e9dbbaa28b954d6997d4154f5.
Revert "Revert "keil c 51""

This reverts commit e2b09bad67e2711635c237a550aeba7fa9093a80.
Revert "keil c 51"

This reverts commit 74f4f12a1e60376e9dbbaa28b954d6997d4154f5.