Time division multiplexing method and system for data bus as well as electronic payment password device

Abstract

The invention suitable for the field of an electronic payment password device provides a time division multiplexing method and system for a data bus as well as the electronic payment password device. The method comprises the following steps: when reading / writing a first chip, controlling a second chip to be in a disable state through a second control line; after reading / writing the first chip, controlling the first chip to be in the disable state through a first control line; and when controlling peripheral equipment, controlling a bus of the first chip to be in a high-resistance state through the first control line, changing bus data according to the need, outputting the bus data to the output end of the second chip, turning off the second chip through the second control line, and latching the output data to the output end of the second chip at the same time. According to the method provided by the invention, the data bus of a digital picture frame microprocessor can be multiplexed to a plurality of equipment in a time-division way, the design is simpler and reliable, and the cost is low.

Description

technical field [0001] The invention belongs to the field of electronic payment ciphers, in particular to a data bus time-division multiplexing method and system and an electronic payment cipher. Background technique [0002] At present, there are a variety of low-cost special-purpose microprocessor chips for certain occasions on the market, such as streaming media chips dedicated to the digital photo frame market. These chips are highly targeted, and the peripherals only support existing applications. Such as SDRAM, SPI FLASH, LCD screen, USB, multi-function card reader, RTC, speaker, AD conversion, etc. If you need to expand multiple devices, you need to add a large number of peripheral logic devices to directly offset the cost of a dedicated microprocessor Advantage. [0003] In addition, large-screen TFT color screens have gradually become a hot spot in the market. 7-inch TFT color screens are mostly used in the development of new products, but most of the microprocesso...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the embodiment of the present invention is to provide a data bus time-division multiplexing method, aiming to solve the problems of high cost and long software development cycle if the existing microprocessor needs to expand peripherals

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