1 files changed, 43 insertions, 0 deletions
diff --git a/pw_chrono_embos/public/pw_chrono_embos/system_clock_config.h b/pw_chrono_embos/public/pw_chrono_embos/system_clock_config.h
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index 000000000..7b2d21a6a
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+++ b/pw_chrono_embos/public/pw_chrono_embos/system_clock_config.h
@@ -0,0 +1,43 @@
+// Copyright 2021 The Pigweed Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy of
+// the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+#pragma once
+
+#include "pw_chrono_embos/config.h"
+
+// embOS does not have an API to determine the tick rate/period at compile time,
+// instead require the user to specify this through the configuration. Note it
+// is configured by the user as Hz, ergo the numerator is always 1.
+#define PW_CHRONO_SYSTEM_CLOCK_PERIOD_SECONDS_NUMERATOR 1
+#define PW_CHRONO_SYSTEM_CLOCK_PERIOD_SECONDS_DENOMINATOR \
+  PW_CHRONO_EMBOS_CFG_CLOCK_PERIOD_SECONDS_DENOMINATOR
+
+#ifdef __cplusplus
+
+#include "pw_chrono/epoch.h"
+
+namespace pw::chrono::backend {
+
+// The embOS clock starts at zero during initialization, approximately the
+// time since boot.
+inline constexpr Epoch kSystemClockEpoch = pw::chrono::Epoch::kTimeSinceBoot;
+
+// The current backend implementation is not NMI safe.
+inline constexpr bool kSystemClockNmiSafe = false;
+
+// The embOS clock halts when the systick interrupt is masked.
+inline constexpr bool kSystemClockFreeRunning = false;
+
+}  // namespace pw::chrono::backend
+
+#endif  // __cplusplus