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interacting with a k6x8008 ram chip

hello everyone, I am reading some code on a system that connect the 8051 with an external ram chip but I have no idea what is going on with the code, I have been struggling on this for quite some time now, just want to see if anyone can point me to the right direction.

the first part i dun understand is how the ram is use

void k6x8008_writebyte (unsigned char hadd,unsigned char madd,unsigned char ladd,unsigned char indat)
{ RD = 1; WR = 1; k6x8008_laddress(ladd); k6x8008_maddress(madd); k6x8008_din(indat); k6x8008_din(indat); k6x8008_haddress(hadd); WR = 0; WR = 0; WR = 1; k6x8008_haddress(0x00); P0 = 0; WR = 1;
}

i don't understand what those ladd, madd or hadd means at all

on the main code this is the part that requires writing data to the ram...

iphadd=((subaddress&HADDBITS)/0x00010000);
ipmadd=((subaddress&MADDBITS)/0x00000100);
ipladd=((subaddress&LADDBITS)/0x00000001); k6x8008_writebyte(iphadd,ipmadd,ipladd+0x00,0xff);
k6x8008_writebyte(iphadd,ipmadd,ipladd+0x01,0xff);
k6x8008_writebyte(iphadd,ipmadd,ipladd+0x02,0xff);

why does the coder uses binary division?? and this might be abstract but im also not sure why he is writing 0xff to the ram in the part above

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  • Managers sees function, not the source code or all the documentation around the code.

    And they pay for a fast delivery of working code.

    The consultant who skips the documentation can offer the lowest price and fastest delivery. (And make the most money by delivering code that no other company is interested in maintaining.)

    In a world where you write your budget based on the initial costs, and ignores the total life-time costs, the buyer tends to get exactly what they are willing to pay for. And the customers does the same - buys the cheapest product. Then they get surprised/frustrated/angry when it doesn't work as well as they hoped.

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  • Managers sees function, not the source code or all the documentation around the code.

    And they pay for a fast delivery of working code.

    The consultant who skips the documentation can offer the lowest price and fastest delivery. (And make the most money by delivering code that no other company is interested in maintaining.)

    In a world where you write your budget based on the initial costs, and ignores the total life-time costs, the buyer tends to get exactly what they are willing to pay for. And the customers does the same - buys the cheapest product. Then they get surprised/frustrated/angry when it doesn't work as well as they hoped.

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