SQL 2012 :: SSIS Passing Parameters To Stored Procedure That Changes Based On The Data Being Passed?

Using the following:

SQL Server: SQL Server 2012
Visual Studio 2012

I have created an SSIS package where I have added an Execute SQL Task to run an existing stored procedure in my SQL database.

General Tab:

Result Set: None
Connection Type: OLE DB
SourceType: Direct Input
IsQueryStoredProcedure: False (this is greyed out and cannot be changed)
Bypass Prepare: True
SQL Statement: EXEC FL_CUSTOM_sp_ml_location_load ?, ?;

Parameter Mapping:

Variable Name Direction Data Type Prmtr Name Prmtr Size
User: system_cd Input NVARCHAR 0 10
User: location_type_cd Input NVARCHAR 1 10

Variables:

location_type_cd - Data type - string; Value - Store (this is static)
system_cd - Data type - string - ??????
The system code changes based on the system field for each record in the load table

Sample Data:

SysStr # Str_Nm
3 7421Store1
3 7454Store2
1815061Store3
1815063Store4
1615064Store5
1615065Store6
1615066Store7
7725155Store8

STORED PROCEDURE: The stored procedure takes data from a load table and inserts it into another table:

Stored procedure variables:
ALTER PROCEDURE [dbo].[sp_ml_location_load]
(@system_cd nvarchar(10), @location_type_cd nvarchar(10))
AS
BEGIN .....................

This is an example of what I want to accomplish: I need to be able to group all system 3 records, then pass 3 as the parameter for system_cd, run the stored procedure for those records, then group all system 18 records, then pass 18 as the parameter for system_cd, run the stored procedure for those records and keep doing this for each different system in the table until all records are processed.

I am not sure how or if it can be done to pass the system parameter to the stored procedure based on the system # in the sys field of the data.