Dram testing method

A method for testing a dynamic random access memory (DRAM) positioned externally from a system on chip (SoC), the SoC comprising a central processing unit (CPU) and a random access memory (RAM), the method comprising:

• copying a test program of the DRAM from the DRAM to the RAM;
• starting the test program in the RAM;
• storing a start physical address and an end physical address of the DRAM in a first register and a second register of the CPU, respectively;
• writing first test data to the start physical address of the DRAM in the first register of the CPU;
• reading second test data from the start physical address of the DRAM;
• determining whether the second test data is the same as the first test data;
• returning a test failure result and ending the test program if the second test data is not the same as the first test data;
• or
• adding a fixed value to the start physical address of the DRAM in the first register to obtain a next start physical address if the second test data is the same as the first test data;
• determining whether the next start physical address is less than the end physical address of the DRAM in the second register;
• writing the first test data to the next start physical address if the next start physical address is less than the end physical address of the DRAM in the second register, and repeating the reading and determining steps;
• or
• returning a test success result and ending the test program if the next start physical address is not less than the end physical address of the DRAM in the second register.