AnsweredAssumed Answered

External RAM Write and Read S12XE

Question asked by Ray Hall on Dec 25, 2015
Latest reply on Dec 29, 2015 by Radek Sestak

I am using the S12XE and LY62W102516 1024K X 16 BIT LOW POWER CMOS SRAM.

 

When I write to the external SRAM and then read back the data, I do not get correct values.

 

Example of write and read.

24 24 24 24 24 24 24 24 24 24  // Write

00 20 24 24 24 24 24 24 24 24  // Read

 

This is the related code.

 

#define  WRITE_BYTE_B(a,d)  *((unsigned char *far)(a+0x200000UL))=d

#define  READ_BYTE_B(a)     *((unsigned char *far)(a+0x200000UL))

 

  uint8_t readStr[16];

 

  for(addr = 0; addr < 10; addr++) {         

     WRITE_BYTE_B(addr,0x24);  // write RAM address

  }

 

  for(addr = 0; addr < 10; addr++) {

    readStr[addr] = READ_BYTE_B(addr);  // read RAM address

  }

 

Ray.

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