A modular banknote apparatus comprising: a banknote acceptor module including an acceptor module PCB; a banknote dispenser module including a dispenser module PCB; at least one banknote storage drum module including a storage drum module PCB (403a, 403b, 403c, 403d); and a banknote transport module including a transport module PCB; wherein: said banknote transport module mechanically and electrically interconnects said at least one banknote storage drum module and said banknote dispenser module; the banknote transport module is configured to provide electronic control of both the banknote dispenser module and the at least one banknote storage drum module in a respective master and slave relationship, wherein the transport module PCB sends operation instructions to the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d), and receives confirmation signals from the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d); and the banknote acceptor module is releasably connected to the banknote transport module, wherein said banknote acceptor module is configured to provide electronic control of the banknote transport module in a master and slave relationship, wherein the transport module PCB receives operation instructions from the acceptor module PCB. a banknote acceptor module including an acceptor module PCB; a banknote dispenser module including a dispenser module PCB; at least one banknote storage drum module including a storage drum module PCB (403a, 403b, 403c, 403d); and a banknote transport module including a transport module PCB; wherein: said banknote transport module mechanically and electrically interconnects said at least one banknote storage drum module and said banknote dispenser module; the banknote transport module is configured to provide electronic control of both the banknote dispenser module and the at least one banknote storage drum module in a respective master and slave relationship, wherein the transport module PCB sends operation instructions to the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d), and receives confirmation signals from the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d); and the banknote acceptor module is releasably connected to the banknote transport module, wherein said banknote acceptor module is configured to provide electronic control of the banknote transport module in a master and slave relationship, wherein the transport module PCB receives operation instructions from the acceptor module PCB. said banknote transport module mechanically and electrically interconnects said at least one banknote storage drum module and said banknote dispenser module; the banknote transport module is configured to provide electronic control of both the banknote dispenser module and the at least one banknote storage drum module in a respective master and slave relationship, wherein the transport module PCB sends operation instructions to the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d), and receives confirmation signals from the dispenser module PCB and the storage drum module PCB (403a, 403b, 403c, 403d); and the banknote acceptor module is releasably connected to the banknote transport module, wherein said banknote acceptor module is configured to provide electronic control of the banknote transport module in a master and slave relationship, wherein the transport module PCB receives operation instructions from the acceptor module PCB.