This Function Won't Work

Hi! all
Can any body help me straighten this function. Just need to get the diffrence between the two time frame in Minutes

CREATE proc setup_DataReport

as
Declare @rc1 int

Declare @rc2 int
Declare @result int

SELECT @rc1 =count(AL_Coming)
FROM Alarm_Log

where convert(char(5),AL_Coming,14) between '09:00' and '10:00' AND
AL_State = 0

SELECT @rc2 = count(AL_Coming)
FROM Alarm_Log

where convert(char(5),AL_Coming,14) between '09:00' and '10:00' AND
AL_State = 1

select @rc1 as a
select @rc1 as a

set @result = sum(@rc1 - rc2)
print @result

go