Description
330130-040-01-00 Multi-function Data Acquisition Device
The system of 330130-040-01-00 is used as an example to illustrate in detail the implementation of this memory expansion method. The system is a multifunctional data acquisition device, capable of 12-bit A/D conversion at a rate of up to 40k times/s, and can save the acquired data into Flash ROM to prevent power-down loss. The technical parameters are as follows: (1) up to 32K bytes of sampling data can be saved; (2) four segments of the system configuration programme can be stored at the same time, 4K bytes per segment, totalling 16K bytes;
Due to the characteristics of 330130-040-01-00 itself, the programming stage after writing data can not be read and write operations, so in order to ensure the normal operation of the system sampling and microcontroller operation, it is necessary to add an additional 32K bytes of RAM as a data cache. 330130-040-01-00’s system programs, interrupt service procedures, etc., take up a total of 56K bytes ( Flash ROM and RAM are each reserved for 28K bytes), for a total storage space requirement of 136K bytes. This demand has exceeded the 64K byte addressing range of the 96 series microcontrollers, for which a memory module was designed
330130-040-01-00 adopts ATMEL’s AT29C1024, with a capacity of 128K bytes and a data line width of 16 bits; the RAM memory consists of two CY7C199s, with a data line width of 16 bits and a capacity of 64K bytes. 80C196 microcontroller’s ALE is the address latched signal, /WE is the write valid signal, /RD is the read The ALE of 80C196 microcontroller is the address latch signal, /WE is the write valid signal, /RD is the read valid signal, and READY is the ready signal. 80C196 microcontroller supports two modes of operation: 8-bit and 16-bit, and in order to improve the performance of the system, it chooses 16-bit operation mode.