1 Introduction Ferroelectric memory (FRAM) is a power-down non-volatile memory introduced by Ramtron in recent years. It combines high performance and low power operation to save data without power. FRAM overcomes the shortcomings of long write time and low erase write time of EEPROM and FLASH. Its price is much lower than that of non-volatile lithium battery SRAM of the same capacity. It has been widely used in subway systems, meter reading systems and IT industry. TMS320VC5402 (hereinafter referred to as C5402) is a cost-effective 16bit fixed-point digital signal processor (DSP) from Texas Instruments, which operates at speeds up to 100MIPS. Its rich internal resource configuration provides a user-configurable system. It is very convenient and has been widely used in communication, electronics, image processing and other fields. However, the C5402 is a RAM-type device that cannot hold any user information after power-off. Therefore, the user needs to put the program code in a non-volatile memory. When the system is powered on, it will be stored externally by executing a bootloader program. The code in the medium is loaded into the C5402 high-speed on-chip memory or the extended memory in the system. After the loading is successful, the code is automatically executed to complete the self-starting. Based on practical experience, this paper introduces the characteristics of a parallel interface ferroelectric memory FM18L08, and also analyzes the characteristics of the C5402 parallel boot loading mode. A design scheme based on the ferroelectric memory FM18L08 and C5402 interfaces is presented. The parallel boot load mode DSP offline independent run system design, and the design has been successfully applied to a voice lock system. 2 FM18L08 Features of FRAM At the heart of Ramtron's FRAM memory technology is the integration of a tiny ferroelectric crystal into a memory cell so that it can operate like a fast, non-volatile RAM. When an electric field is applied to the ferroelectric crystal, the central atom moves in the direction of the electric field. The electric field is removed, the central atom remains stationary, and the state of the memory is saved. The FRAM memory does not need to be refreshed periodically, and the data is saved immediately after the power is turned off. FM18L08 is a 32K ╳8bits FRAM introduced by Ramtron in recent years. Its main features are as follows: 3.0-3.65V single power supply; parallel interface; available in SOIC and DIP packages; low power consumption, quiescent current less than 15uA, The read/write current is less than 10mA; non-volatile, the data can be stored for 10 years after power failure; read and write unlimited times. The pin structure of FM18L08 is shown in Figure 1: /CE: Chip Select / WE: Write Enable / OE: Output Enable A0-A14: Address Terminal DQ0-DQ7: Data Terminal VDD: Power VSS: Ground Blinking LED Lamps Blinking LED Lamps,Flashing LED Lamps,Orange Flashing LED Lamps,Flashing Blue LED Lamps Shenzhen Best LED Opto-electronic Co.,Ltd , https://www.bestsmd.com
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