Using External Memory with PIC24F/24H/dsPIC33F ... - Microchip

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AN1210 MemBulkRead API The API MemBulkRead reads a sequence of a specified length of data from the specified address, and stores it in a specified array. The inputs for this API are the starting memory address (24 bits) from where the data has to be read, the number of data bytes (maximum 64 Kbytes) to be read and the address of the array (of char) where the read data needs to be stored. This API returns nothing; it stores the read data in the passed array. Figure 20 illustrates the flow of the MemBulkRead API. FIGURE 21: MemBulkRead API FLOWCHART MemBulkRead Select address auto-increment. Load address_low to Address register (PMADDR) and address_high to Address High register. Enable the chip select port of the respective chip select. Is PMP Busy? Read PMP Data (Dummy Read) Is Buffer Full? No Is PMP Busy? No No Read PMP Data and Save in Buffer Load the address_high to Address High register. Enable the chip select port of the respective chip select. DS01210A-page 28 © 2008 <strong>Microchip</strong> Technology Inc. Yes Yes Yes Return
MemByteWrite API The API, MemByteWrite, writes a byte to the specified address. The inputs for this API are the memory address (24 bits) where the data has to be written and the data (8 bits) that needs to be written. This API returns nothing. Figure 22 illustrates the flow of the MemByteWrite API. FIGURE 22: MemByteWrite API FLOWCHART MemByteWrite Load the address_low to Address register (PMADDR) and address_high to Address High register. Enable the chip select port of the respective chip select. Is PMP Busy? Write PMP Data Return AN1210 © 2008 <strong>Microchip</strong> Technology Inc. DS01210A-page 29 No Yes
Page 1 and 2: Author: Vidyadhar Vivekananda Micro
Page 3 and 4: FIGURE 1: MEMORY INTERFACE PMP PINS
Page 5 and 6: FUNCTIONAL IMPLEMENTATION This sect
Page 7 and 8: Interfacing a 32K x 8-Bit Memory De
Page 9 and 10: PARTIALLY MULTIPLEXED MODE In Parti
Page 11 and 12: FULLY MULTIPLEXED MODE In fully mul
Page 13 and 14: Interfacing Two 16K x 8-Bit Memory
Page 15 and 16: Interfacing a 32K x 16-Bit Word Mem
Page 17 and 18: AN1210 FIGURE 12: READ TIMING WHEN
Page 19 and 20: EXPANSION OF EXTERNAL MEMORY Extern
Page 21 and 22: Interfacing Multiple Memory Devices
Page 23 and 24: REFERENCE CODE This section describ
Page 25 and 26: Memory Interface Application File E
Page 27: MemByteRead API The API, MemByteRea
Page 31 and 32: CONCLUSION This application note di
Page 33 and 34: Note the following details of the c

Using External Memory with PIC24F/24H/dsPIC33F ... - Microchip

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