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246 | ------------------------------------------------------------------------------
-- --
-- Copyright (C) 2016-2020, AdaCore --
-- --
-- Redistribution and use in source and binary forms, with or without --
-- modification, are permitted provided that the following conditions are --
-- met: --
-- 1. Redistributions of source code must retain the above copyright --
-- notice, this list of conditions and the following disclaimer. --
-- 2. Redistributions in binary form must reproduce the above copyright --
-- notice, this list of conditions and the following disclaimer in --
-- the documentation and/or other materials provided with the --
-- distribution. --
-- 3. Neither the name of the copyright holder nor the names of its --
-- contributors may be used to endorse or promote products derived --
-- from this software without specific prior written permission. --
-- --
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS --
-- "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT --
-- LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR --
-- A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT --
-- HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, --
-- SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT --
-- LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, --
-- DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY --
-- THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT --
-- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE --
-- OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. --
-- --
------------------------------------------------------------------------------
with nRF.Clock;
with nRF.Device; use nRF.Device;
with nRF.RTC; use nRF.RTC;
with nRF.Events;
with nRF.Interrupts;
with System.Machine_Code; use System.Machine_Code;
package body MicroBit.Time is
package Clocks renames nRF.Clock;
Clock_Ms : Time_Ms := 0 with Volatile;
Period_Ms : constant Time_Ms := 1;
Subscribers : array (1 .. 10) of Tick_Callback := (others => null);
procedure Initialize;
procedure Update_Clock;
procedure RTC1_IRQHandler;
----------------
-- Initialize --
----------------
procedure Initialize is
begin
if not Clocks.Low_Freq_Running then
Clocks.Set_Low_Freq_Source (Clocks.LFCLK_SYNTH);
Clocks.Start_Low_Freq;
loop
exit when Clocks.Low_Freq_Running;
end loop;
end if;
Stop (RTC_1);
-- 1kHz
Set_Prescaler (RTC_1, 0);
Set_Compare (RTC_1, 0, 32);
Enable_Event (RTC_1, Compare_0_Event);
nRF.Events.Enable_Interrupt (nRF.Events.RTC_1_COMPARE_0);
nRF.Interrupts.Register (nRF.Interrupts.RTC1_Interrupt,
RTC1_IRQHandler'Access);
nRF.Interrupts.Enable (nRF.Interrupts.RTC1_Interrupt);
Start (RTC_1);
end Initialize;
------------------
-- Update_Clock --
------------------
procedure Update_Clock is
begin
Clock_Ms := Clock_Ms + Period_Ms;
end Update_Clock;
---------------------
-- RTC1_IRQHandler --
---------------------
procedure RTC1_IRQHandler is
begin
Stop (RTC_1);
Clear (RTC_1);
Start (RTC_1);
nRF.Events.Clear (nRF.Events.RTC_1_COMPARE_0);
Update_Clock;
for Subs of Subscribers loop
if Subs /= null then
-- Call the subscriber
Subs.all;
end if;
end loop;
end RTC1_IRQHandler;
-----------
-- Clock --
-----------
function Clock return Time_Ms is
begin
return Clock_Ms;
end Clock;
--------------
-- Delay_Ms --
--------------
procedure Delay_Ms (Milliseconds : UInt64) is
Wakeup_Time : constant UInt64 := Clock + Milliseconds;
begin
while Wakeup_Time > Clock loop
Asm (Template => "wfi", -- Wait for interrupt
Volatile => True);
end loop;
end Delay_Ms;
-----------------
-- Tick_Period --
-----------------
function Tick_Period return Time_Ms is
begin
return Period_Ms;
end Tick_Period;
--------------------
-- Tick_Subscribe --
--------------------
function Tick_Subscriber (Callback : not null Tick_Callback) return Boolean is
begin
for Subs of Subscribers loop
if Subs = Callback then
return True;
end if;
end loop;
return False;
end Tick_Subscriber;
--------------------
-- Tick_Subscribe --
--------------------
function Tick_Subscribe (Callback : not null Tick_Callback) return Boolean is
begin
for Subs of Subscribers loop
if Subs = null then
Subs := Callback;
return True;
end if;
end loop;
return False;
end Tick_Subscribe;
----------------------
-- Tick_Unsubscribe --
----------------------
function Tick_Unsubscribe (Callback : not null Tick_Callback) return Boolean is
begin
for Subs of Subscribers loop
if Subs = Callback then
Subs := null;
return True;
end if;
end loop;
return False;
end Tick_Unsubscribe;
---------------
-- HAL_Delay --
---------------
Delay_Instance : aliased MB_Delays;
function HAL_Delay return not null HAL.Time.Any_Delays is
begin
return Delay_Instance'Access;
end HAL_Delay;
------------------------
-- Delay_Microseconds --
------------------------
overriding
procedure Delay_Microseconds (This : in out MB_Delays;
Us : Integer)
is
pragma Unreferenced (This);
begin
Delay_Ms (UInt64 (Us / 1000));
end Delay_Microseconds;
------------------------
-- Delay_Milliseconds --
------------------------
overriding
procedure Delay_Milliseconds (This : in out MB_Delays;
Ms : Integer)
is
pragma Unreferenced (This);
begin
Delay_Ms (UInt64 (Ms));
end Delay_Milliseconds;
-------------------
-- Delay_Seconds --
-------------------
overriding
procedure Delay_Seconds (This : in out MB_Delays;
S : Integer)
is
pragma Unreferenced (This);
begin
Delay_Ms (UInt64 (S * 1000));
end Delay_Seconds;
begin
Initialize;
end MicroBit.Time;
|