Hello,
I am writing a whole new BIOS, from scratch, for the 5162. The already existing BIOS is on chips U34 and U35. Normally, exactly one byte (the odd byte) should be on U34, followed by exactly one even byte on U35, but this is not always the case. By examining the machine code and data in a hex viewer, and comparing them to the listing, I discovered that generally there is a one and one succession, as I expected, but not always. In around 10% of the cases, there are two consecutive bytes on U34, followed by two consecutive bytes on U35, especially in proximity of the mov B8 instruction, but not only. But two consecutive bytes mean 16-bit, while the chip transmission should occur only as an eight bit one..
Does somebody know why is like this and what is the real criterion of splitting between odd and even? I am asking, because I will have to transfer my BIOS on the odd and even chips, by splitting them in the correct sequence between the two. Thanks a lot!
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