Method for sharing spi interface bus by multiple devices

Abstract

The invention discloses a method for sharing a spi interface bus by multiple devices, clock input ports of all spi interface devices are directly connected with spi interface clock signals, each data port is directly connected with corresponding spi interface data signals, only a chip selection input port of a spi device with a control function is directly connected with a spi interface chip selection signal line, chip selection signal lines of other devices are indirectly connected with spi interface chip selection signals through a gating electronic device, and a gating path of the gating electronic device is controlled by the spi device which is directly connected with spi interface chip selection. The invention relates to the field of spi communication interface use methods, password module use, electronic device data encryption and sensitive information protection design, in particular to a method for multiple devices to share a spi interface bus.

Description

technical field [0001] The invention relates to a method for using an SPI communication interface, a use of a password module, data encryption of an electronic device, and the fields of sensitive information protection design, and specifically refers to a method for sharing an SPI interface bus with multiple devices. Background technique [0002] spi is the abbreviation of Serial Peripheral Interface. It is divided into two types: spi master and spi slave. Because it occupies relatively few signal lines, is easy to use and reliable in operation, it is widely integrated into various in a chip. Generally, most of the chips that play the role of master control in electronic information equipment are integrated with spi master interface, or both spi master interface and spi slave device interface are supported, such as central processing unit (CPU), application processor (AP), MCU, DSP Most of them are integrated with spi master interface; most of the auxiliary chips are integr...

AI Technical Summary

Problems solved by technology

[0003] Due to the wide use and large number of spi interface devices, and the limited number of spi main interfaces of the main control chip, when the number of spi devices required by electronic information equipment exceeds a certain number, some main control chips are inevitably stretched and can only be replaced with supported ones. The main control chip with more SPI interfaces will increase the design workload and even prolong the project cycle

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