The present invention relates to a payment module implementing a MDB TRANSACTION STRING in memory to effectuate cashless vending. The MDB TRANSACTION STRING allows the payment module and or computing platform to manage cashless vending by monitoring data fields within the MDB TRANSACTION STRING.The MDB TRANSACTION STRING is constructed and managed in payment module memory. The MDB TRANSACTION STRING includes at least one of the following data fields a VEND STATE field, a MAX VEND SALE field, a SALE PRICE field, a COLUMN field, or a VEND FLAG field.In operation, the payment module obtains data from a vending machine and constructs and manages an MDB TRANSACTION STRING in memory. Utilization of the MDB TRANSACTION STRING occurs when the payment module application code and or a computing platform interconnected with the payment module reads the MDB TRANSACTION STRING to make certain determinations to effectuate cashless vending.