There's this string at the end: AWAITING APPLE INPUT Rev 1.1
Just glancing at the ROM, I think the string is two strings, since there's a null terminator in between them. The first string being in ALL CAPS suggests that the boot ROM's "display message" routine was used to show that on the display, and sure enough, you can find 4eb9 00fe 0088 (JSR #$FE0088 ; call the display message routine) elsewhere in the hex.
The phrase "AWAITING APPLE INPUT" is interesting, since in the Monitor (and elsewhere?), an "Apple" usually referred to an Apple II that was part of the development workstation (see e.g. Page 6 of
this Monitor manual). So maybe another computer was involved somehow.
Page 86 of the manual describes a LISATEST program (presumably different from the LisaTest most of us know) that contains an "Apple-Lisa Interface Test". The description:
The Interface Test attempts to use the parallel port interface between the Apple II and the Lisa to verify that the two systems can communicate with each other.
Based on the Page 6 diagram, though, I think the Apple talked to the Lisa through the Lisa's own parallel port.
Or wait, maybe not...
These release notes for the earlier 11.6 Monitor talk about "an Apple PIA card". (Note that when the docs talk about a "Built-In Profile", I think they mean the internal parallel port, not Widget; also, I think an "I/O port" is a logical numbering scheme within the Monitor and not the expansion slots.)
Now I'm starting to wonder if this is what the rudimentary parallel port card that started this thread was all about---maybe that's an Apple PIA card we're looking at. It fits the story in a way---they would have needed to have the PIA card from very early on, so it makes sense for it to be uncomplicated. One could examine the
Monitor source code to see if the code for talking to the Apple is compatible with the very simple card we see in blusnowkitty's pictures.
Anyway, my reason for going down this road was to wonder whether one of the connectors on the I/O test card may have been for talking to the Apple. I'm starting to think not, so the question remains---in AWAITING APPLE INPUT, who is the APPLE, what is it saying, and how does the test card get the message? I guess the real thing to do is disassemble that ROM data and find out :-)