Half-message based multiplex communication interface circuit which uses a main microcontroller to detect a match in addresses and generate a qualified signal
First Claim
1. A method for receiving frame messages communicated to one or more nodes, each controlled by a microcontroller, along a common transmission line of a multiplex communications system, comprising the steps of:
- (a) receiving type and target bytes and responsive thereto generating a first interrupt signal to the microcontroller,(b) commanding the microcontroller, responsive to receiving the first interrupt signal, for qualifying the frame message by retrieving and matching one or more of the type and target bytes with corresponding bytes stored therein, and responsive thereto generating a qualified signal,(c) receiving and storing data bytes from the frame message into temporary memory for subsequent processing only responsive to receiving the qualified signal from the microcontroller,(d) calculating a CRC value from, and generating a corresponding CRC signal representative of, the integrity of the data bytes received from the frame message; and
(e) generating a second interrupt signal, responsive to receiving a valid CRC signal, for commanding the microcontroller to fetch the data bytes.
6 Assignments
0 Petitions
Accused Products
Abstract
A method and circuit for receiving frame messages connected to one or more nodes, each controlled by a microcontroller, along a common transmission line of a multiplex communication system. The method includes the steps of: (a) receiving the type and target bytes, and responsive thereto generating a first interrupt signal to the microcontroller at the node; (b) commanding the microcontroller, responsive to receiving the first interrupt signal, for qualifying the frame message by retrieving and matching one or more of the type and target bytes with corresponding bytes stored in programmable memory within the microcontroller, and responsive thereto generating a qualified signal; and (c) receiving data bytes from the frame message only responsive to receiving the qualified signal from the microcontroller.
26 Citations
32 Claims
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1. A method for receiving frame messages communicated to one or more nodes, each controlled by a microcontroller, along a common transmission line of a multiplex communications system, comprising the steps of:
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(a) receiving type and target bytes and responsive thereto generating a first interrupt signal to the microcontroller, (b) commanding the microcontroller, responsive to receiving the first interrupt signal, for qualifying the frame message by retrieving and matching one or more of the type and target bytes with corresponding bytes stored therein, and responsive thereto generating a qualified signal, (c) receiving and storing data bytes from the frame message into temporary memory for subsequent processing only responsive to receiving the qualified signal from the microcontroller, (d) calculating a CRC value from, and generating a corresponding CRC signal representative of, the integrity of the data bytes received from the frame message; and (e) generating a second interrupt signal, responsive to receiving a valid CRC signal, for commanding the microcontroller to fetch the data bytes. - View Dependent Claims (2, 3, 4)
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5. An interface device, interposed between a transmission line of a multiplex communications system and a microcontroller, for receiving frame messages communicated to one or more nodes, said interface device comprising in combination:
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a qualification memory coupled to the transmission line for receiving type and target bytes of the frame message, and responsive thereto generating a first interrupt signal; an interface controller, coupled to said qualification memory and the microcontroller, for commanding, responsive to receiving said first interrupt signal, the microcontroller to retrieve and match one or more of the type and target bytes with corresponding bytes stored in the microcontroller and responsive thereto generating a qualified signal; and a receive memory for receiving and storing, responsive to receiving said qualified signal, data bytes of the frame message, whereby the data bytes of the frame message are received in said receive memory but stored only responsive to the microcontroller generating said qualified signal. - View Dependent Claims (6, 7, 8, 9)
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10. A method for receiving frame messages communicated to one or more nodes, each controlled by a microcontroller, along a common transmission line of a multiplex communications system, comprising the steps of:
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(a) receiving type and target bytes in a qualification memory and responsive thereto generating a first interrupt signal, (b) commanding the microcontroller, responsive to receiving the first interrupt signal, to qualify the frame message by retrieving, from the qualification memory, and matching one or more of the type and target bytes with corresponding bytes stored therein, and responsive thereto generating a qualified signal; and (c) receiving and storing data bytes in receive memory only responsive to receiving the qualified signal from the microcontroller, whereby the data bytes from the frame message are stored only after qualification of the type and target bytes. - View Dependent Claims (11, 12, 13, 14)
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15. An interface device, interposed between a microcontroller and a transmission line, for receiving frame messages communicated to one or more nodes along the transmission line in a multiplex communications system, comprising in combination:
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a qualification memory coupled to the transmission line for receiving type and target bytes of the frame message, and responsive thereto generating a first interrupt signal; an interface controller, coupled to said qualification memory and the microcontroller, for commanding, responsive to receiving said first interrupt signal, the microcontroller to retrieve and match one or more of the type and target bytes with corresponding bytes stored in the microcontroller and responsive thereto generating, before reception of the data bytes in the message frame is complete, a qualified signal; and a receive memory, coupled to said interface controller and the transmission line, for receiving and then storing, only responsive to receiving said qualified signal, data bytes of the frame message, whereby the microcontroller qualifies, before reception of the data bytes is complete, the frame message using only the type and target bytes. - View Dependent Claims (16, 17, 18, 19, 20)
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21. A method for receiving frame messages communicated to one or more nodes, each controlled by a microcontroller, along a common transmission line of a multiplex communications system, comprising the steps of:
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(a) receiving type and target bytes in a qualification memory and responsive thereto immediately generating a first interrupt signal, (b) commanding the microcontroller, responsive to receiving the first interrupt signal, to qualify the frame message by retrieving, from the qualification memory, and matching one or more of the type and target bytes with corresponding bytes stored in the microcontroller, and responsive thereto generating a qualified signal; and (c) receiving and storing data bytes in receive memory only responsive to receiving the qualified signal from the microcontroller, whereby the data bytes from the frame message are stored only after qualification of the frame message through the type and target bytes. - View Dependent Claims (22, 23, 24, 25)
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26. An interface device, interposed between a microcontroller and a transmission line, for receiving frame messages communicated to one or more nodes along the transmission line in a multiplex communications system, comprising in combination:
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a qualification memory coupled to the transmission line for receiving only the type and target bytes of the frame message, and the promptly generating a first interrupt signal responsive thereto; an interface controller, coupled to said qualification memory and the microcontroller, for commanding, responsive to receiving said first interrupt signal, the microcontroller to retrieve and match one or more of the type and target bytes with corresponding bytes stored in the microcontroller and then promptly generating a qualified signal responsive thereto; and a receive memory, coupled to the transmission line and the microcontroller, for receiving and storing, responsive to receiving said qualified signal, data bytes from the frame message, whereby the microcontroller qualifies the frame message after receiving only the type and target bytes. - View Dependent Claims (27, 28, 29, 30, 31, 32)
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Specification