Quoted from barakandl:
Use the file size of the image to decide what ROM to use. In windows it shows bytes so mutiply by eight. If your file is 128KB in windows explorer would go fit on a 1Mbit 27C010 but you could also use any of the other 32pin JEDEC standard pin out EPROMs as a replacement IE 27C040. Just fill up the EPROM with repeated copies of data until full.
Here is a chart on wikipedia that will help pick an EPROM based on the file size.
Got it, and that Wikipedia chart looks super useful. I will pay attention to the image file size, and pick an EPROM that can handle that size, or larger with the same pin count package.
Using this info has now helped me identify why I'm having trouble figuring out in advance how to burn a U7 Bootflash EPROM to update the Sound OS on my LOTR before installing the LOTR LE 10.02 CPU code in preparation for adding a shaker. The file image I was intending to use to burn the U7 Bootflash EPROM is named BIOSv8.u8 and is 128KB in size. I got that file per this Pinside reference: https://pinside.com/pinball/forum/topic/how-to-install-shaker-motor-in-lotr-standard-edition/page/5#post-3080604. That must not be the correct file because a 128KB file would require a 1Mbit chip or larger, but a 1MB chip is not the correct pin count package (too big) to fit into the 28 pin socket at U7. So, I will start the search again for the correct image file for the U7 Bootflash EPROM, and when I find that then I can burn it to a 28 pin EPROM of the appropriate size (or larger including repeat copies to bulk up the file image).
Unless this is indeed the correct file, and there is a different reason why it shows at 128KB on my computer's hard drive?