Stored Procedure With Input Going To A Temp Table

Could someone help me get this stored procedure to work? I want to give the stored procedure a long list of departments and have them added to a temp table. This only gets the first dept. in the temp table. I'm confused. Open to other suggestions, but want to use a 1col temp table to hold the depts.

After this is done, an SQL query is run using the temp table.
Input for test:
--csi_crystal_xxxx "pc9xp,pc8,pc7,pc6,pc6543,pc945678"
--select * from ##CrystalGetCosts

create procedure csi_crystal_xxxx

@DeptResp varchar(4000)
AS
SET NOCOUNT ON
DECLARE @SQL varchar(8000)
DECLARE @Dept varchar(10)
DECLARE @iLen int
DECLARE @iPtr int
DECLARE @iEnd int

If Exists (Select name, Type From [tempdb]..[sysobjects]
where name = '##CrystalGetCosts' And Type = 'U')
Drop table ##CrystalGetCosts

CREATE TABLE ##CrystalGetCosts (Dept_Resp_No varchar(10))
Set @iLen=Len(@DeptResp)
Set @iPtr = 1
While @iPtr < @iLen
BEGIN
SET @iEND = charindex(',',@DeptResp,@iPtr)
Set @Dept= Substring (@DeptResp,@iPtr,@iEnd-1)
INSERT INTO ##CrystalGetCosts Values (@Dept)
Set @iPtr = @iEnd + @iLen
END