Half duplex link with isochronous and asynchronous arbitration

A memory system, comprising:

• an Input Output (IO) unit;
• a memory controller;
• a half duplex link coupled between said IO unit and said memory controller, information flowing over said half duplex link being divided into a plurality of service periods;
• and
• an arbitration unit coupled between said IO unit and said memory controller, said arbitration unit being configured to (1) schedule an isochronous transaction in service period N if the isochronous transaction is ready to be serviced before service period N at one of said IO unit and said memory controller and (2) schedule, in service period N, an asynchronous transaction ready to be serviced at one of said IO unit and said memory controller if no isochronous transaction is ready to be serviced before service period N.

A memory system, comprising:

• an Input Output (IO) unit;
• a memory controller;
• a half duplex link coupled between said IO unit and said memory controller, information flowing over the half duplex link being divided into a plurality of service periods;
• a first arbitration unit associated with said IO unit and configured to (1) schedule an isochronous transaction in service period N if the isochronous transaction is ready to be serviced before service period N at one of said IO unit and said memory controller and (2) schedule, in service period N, an asynchronous transaction ready to be serviced at one of said IO unit and said memory controller if no isochronous transaction is ready to be serviced before service period N;
• and
• a second arbitration unit associated with said memory controller and configured to (1) schedule an isochronous transaction in service period N if the isochronous transaction is ready to be serviced before service period N at one of said IO unit and said memory controller and (2) schedule, in service period N, an asynchronous transaction ready to be serviced at one of said IO unit and said memory controller if no isochronous transaction is ready to be serviced before service period N.