how can pass datetime as a input parameter for stored procedure

alter procedure sp_retreivesmsvalue(@stid int,@currenttime datetime)
as
declare @receiverid int
declare @time datetime
declare @time1 time(7)
declare @date varchar(10)
set nocount on
begin
--set @time=@currenttime
select @receiverid=Contact_id from Student_Contact_details where Student_id=@stid
SELECT @time= Convert(char(2),DATEPART(hour,@currenttime)) + ':'+convert(char(2),datepart(mi,@currenttime)) + ':' + convert(char(2),datepart(S,@currenttime))
set @time1=CONVERT(time(7),@time)
declare @intimemorning1 time(7),@intimemorning2 time(7)
declare @outtimeevening1 time(7),@outtimeevening2 time(7)
declare @outtimenoon1 time(7),@outtimenoon2 time(7)
declare @workingdaytype varchar(50)
set @intimemorning1='06:00:00'
set @intimemorning2='09:30:00'
set @outtimeevening1='16:15:00'
set @outtimeevening2='23:30:00'
--select  DATEADD(D,0,DATEDIFF(D,0,GETDATE()))--from Workingday_details
SELECT @date= CONVERT(date,@currenttime,111) from Workingday_details where Working_date=@currenttime
select @workingdaytype= Workingday_type from Timetemplate_details where Time_id in(select Time_id from Workingday_details where Working_date=@date)
if @workingdaytype='full day'
begin
if @time1 between @intimemorning1 and @intimemorning2
begin
select m.Receiver_id,t.Template,t.Template_id,k.Phone_number from Message_configuration_details m inner join Message_template_details t on m.Template_id=t.Template_id inner join Student_Contact_details k on m.Receiver_id=k.Contact_id where t.Template_id='201' and m.Receiver_id=@receiverid

end
if @time1 between @outtimeevening1 and @outtimeevening2
begin
select m.Receiver_id,t.template,t.Template_id ,k.Phone_number from Message_configuration_details m inner join Message_template_details t on m.Template_id=t.Template_id inner join Student_Contact_details k on m.Receiver_id=k.Contact_id where t.Template_id=202 and m.Receiver_id=@receiverid
end


--SELECT CONVERT(VARCHAR(10),GETDATE(),103)
--select CONVERT(date,getdate(),111)
end
end