I do have these ROM files.
Odd that they contain multiple sets of BIOS expansion ROM code:
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PHX150I.BIN (32 KB) has two sets of BIOS expansion ROM code in it:
* 8 KB sized (ROM size byte = 10h) starting offset 0000. Contains "PHX150I". Checksum = 0C6D00.
* 24 KB sized (ROM size byte = 30h) starting offset 2000. Contains "PHX169K". Checksum = 307A00.
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PHX150G.BIN (32 KB) has three sets of BIOS expansion ROM code in it:
* 8 KB (ROM size byte = 10h) sized starting offset 0000. Contains "PHX150G". Checksum = 0C2600. Identical to the 8 KB sized PHX150G at minuszerodegrees.net
* 23 KB (ROM size byte = 2Eh) sized starting offset 2000. Contains "PHX169F". Checksum = 2DDC00.
* 1 KB (ROM size byte = 02h) sized starting offset 7C00. Contains "PHX141A" and "PHX145A" and "PHX120AU". Checksum = 015100.
Most computers will not 'discover' the third code set because its address is not a multiple of 2 KB. Maybe it does not matter in this case.
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