Implementation method of double-port RAM mutual exclusion access

Abstract

The invention relates to an implementation method of double-port RAM mutual exclusion access. The method comprises the following operation steps: 1) dividing a shared data area into a plurality of data areas by an address partitioned mode, and establishing a corresponding software protocol; 2) dividing a shared storage area of a RAM into a plurality of large data areas starting from an initial unit according to the type of exchange data in software partition processing; determining size of the data areas based on practical transmission data; and subdividing the large data areas into a data receive buffer area and a data send buffer area, and defining each buffer area with corresponding data access base addresses and read-write pointers; and 3) in the system, all the communication work of an external system is completed by a slave, while a host is only required to write the date to be sent into the corresponding data buffer area in the double-port RAM or read the required data.

Description

technical field [0001] The invention relates to a method for realizing mutually exclusive access of a dual-port RAM, which belongs to the field of processor signal exchange. Background technique [0002] In modern industrial control systems, due to the increasingly high requirements for system functions and performance, high-performance processors are generally used to realize control functions, and these intelligent devices are networked to form a distributed system. As a shared memory, dual-port RAM is more and more widely used in control systems that meet high real-time requirements and large data volumes. [0003] Generally, dual-port RAM provides two completely independent ports, and each port has its own control line, address line and data line. However, when two CPUs write data to the same address unit at the same time, or two CPUs operate on the same address unit at the same time, one writes data and the other reads data, the dual-port RAM will have a sharing confli...

AI Technical Summary

Problems solved by technology

[0015] Interruption anti-conflict mode: When an interruption occurs, the current execution process will be interrupted, resulting in an uncertain running process

[0016] Anti-collision method of inserting waiting state: For high-speed interfaces, it will affect the data transmission rate, and in this method, the CPU needs to check the BUSY signal and make a judgment when accessing data, and there may be a waiting situation

It is difficult to meet the requirement of time determinism

[0017] Semaphore anti-collision mode: when two CPUs share the memory space, if the dual-port RAM is mainly used to exchange data between the two CPUs, it is difficult to guarantee the real-time exchange by software

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