Method and device for expanding internal integrate circuit bus

Abstract

The invention relates to a method and a device used for extending internal integrated circuit bus; wherein, the method comprises the steps as follows: the serial clock wire of the internal integrated circuit I<2>C bus is extended as a plurality of serial clock wires by a strobe multiplexer; a plurality of serial clock wires are connected with all slave devices; the serial data wires of the I<2>C are directly connected with all slave devices; the device comprises a strobe multiplexer which is connected with a controller by a PIO wire and a serial clock wire of the I<2>C bus; the strobe multiplexer is connected with all slave devices by the extended serial clock wires; the controller is directly connected with all slave devices by the serial data wires of the I<2>C. the extension of I<2>C bus in a modularization design system is achieved by a simple logic device strobe multiplexer, usage of an expensive programmable I<2>C extension device is avoided, the extension cost of the I<2>C bus and the cost of the modularization design system are greatly reduced, and the method and the device are suitable for environments where the cost is strictly controlled.

Description

technical field [0001] The present invention relates to the technical field of electronic system application design, in particular to an extended internal integrated circuit (Inter-Integrated Circuit, I 2 C) bus method and device. Background technique [0002] Bus (Bus) refers to a group of transmission lines that transmit information from one or more source components to one or more destination components by time-division multiplexing. According to the way of transmitting data, it can be divided into serial bus and parallel bus. In a serial bus, binary data is sent to the destination device bit by bit through a data line; in a parallel bus, there are usually more than 2 data lines. [0003] I 2 The C bus is a simple bidirectional two-wire serial bus developed by Philips for effective control between microelectronic devices or components. each connected to the I 2 The devices of the C bus can be set by the unique address set by the hardware and the simple host / slave rel...

AI Technical Summary

Problems solved by technology

[0010] Extending I with Logic Devices 2 The disadvantage of the C bus is that: due to the I 2 The serial clock line of the C interface is connected to the same clock line pin of the logic device, and the pin of each device has a certain capacitive impedance (generally around 10pF), when there are many slave devices (more than 8 ), on the one hand, the capacitive load of the clock signal line will increase to a larger value, because the capacitive load can prevent the level jump, which will prevent the level from sending a fast jump, when the signal level is from 0 to 1 jump, the jump edge (rising edge) will become very slow; on the other hand, when the number of devices increases, when the signal level jumps, multiple slave devices will simultaneously reflect the jump signal multiple times, and the original The slowly rising signal pulls back to a lower level

This signal distortion (Distortion) may make the receiver data sampling error, because there is a back groove on the clock edge, the receiver may misjudge two rising clock edges, and the slave device samples data on the rising edge of the clock , so the slave device oversamples the data, causing the I 2 C communication error, resulting in unpredictable consequences

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