Data bus with client-aborted message handling method
AssigneeAnalog Devices, Inc.
InventorsSteven E. Austin, Dale F. Stolitzka
Life of this patent
Estimating the term…
Abstract
A data bus and message handling method provide a definitive means of indicating a client-aborted message for data bus systems which employ a message protocol that requires each message conveyed between a client device and an originating device to automatically and atomically include a frame check sequence (FCS). When a message is not to be client-aborted, a ‘good’ FCS is generated by a first method, typically based on the message's data content. However, when a message is to be client-aborted, the FCS is generated by a second method which requires modifying the good FCS value to create a ‘bad’ FCS, preferably using a mathematical means that preserves the uniqueness of the bad FCS to a high degree.
Claims20
A data bus system arranged to convey messages between originating and client device connected to a data bus and which employs a message protocol that requires each message conveyed between a client device and an originating device to include a frame check sequence (FCS) comprising:
- A data bus for conveying message between devices connected to said data bus;
- An originating device connected to said data bus and arranged to initiate data bus transactions with other devices connected to said data bus;
- and
- At least one client device connected to said data bus and arranged to automatically and atomically include a frame check sequence (FCS) with each message convey between said client device and said originating device;
- said data bus system arranged when a message to be conveyed to said originating device is not to be client-aborted, the FCS of said message is generated by a first method known to both client and originating devices, said FCS generated by said first method indicating to said originating device whether said conveyed message is ‘good’ or ‘failed’, and when a message to be conveyed to said originating device is to be client-aborted, the FCS of said message is generated by said first method and then modified using a second method, said modified FCS conveyed with said message to said originating device.
A method of handling client-aborted message for a data bus system arranged to convey message between originating and client device connected to a data bus and which employs a message protocol that requires each message conveyed between a client device and an originating device to include a frame check sequence (FCS) comprising:
- Initiating by an originating device, a data bus transaction with a client device arranged to automatically and atomically include a frame check sequence (FCS) within each message conveyed between said client device and said originating device;
- Generating said FCS by a first method known to both said client and originating devices when a message conveyed between said client and originating device is not to be client-aborted, said FCS generated by said first method indicating to said originating device whether said conveyed message is ‘good’ or ‘failed’;
- and
- Generating said FCS by said first method and then modifying said FCS using a second method when a message conveyed between said client and originating device is to be client-aborted and conveying said modified FCS with said message to said originating device.
Dependencies are inferred from the claim text.