About the pinouts, lets start where the story begin:
2708 (1Kbytes) and olders (2704, 2702) are the great-grandfather of all ROM chips what we using.

These use three power lines (+5V,-5V,+12V), then can not be used in modern computer systems such as the Enterprise.
But look the pinout: Data and Address lines positions will be standard for the many next generation!
The next generation of the 24 pins EPROMs the 2716, 2732 (2K,4K):


These the first single power line EPROMs. Another change now the chips have separate Chip Enable and Output Enable signals, this is will be standard for the future generations.
In Enterprise systems only printers using this small capacity chips. (At ZX Spectrum and Commodore systems many hw using this type.)
Because all pins used at 2732 the next step need a longer package then 2764 (8K) are the first 28 pins EPROM.

In Enterprise only used at some early EP64 machines where the IS-BASIC stored in 2x8K EPROMs.
The next series the 27128 (16K) and 27256 (32K) the usually used when the Enterprise born.


-motherboard have a 32K socket
-one socket cartridges have a 32K socket
-two sockets cartridges jumperable 8K/16K. Some early EP64 machines have the 2x8K configuration, later machines and all English EP128 machines got a one socket cartridges with 16K ROM chip. German EP128 machines have a mixed cartridges: two sockets type with 2x16K ROM, or one socket type with 32K ROM.
-EXDOS card have a jumperable 16K/32K socket, the standalone card with 1.0 version are 16K, built in card in the German floppy units have a version 1.3 ROM which are 32K
-third party EXDOS cards have a 32K socket, MICROTEAM type have a 3x32K socket
-the Plus cartridge from the 'a' Studio have a 2x16K and 1x32K sockets
-exist a third party cartridge with 3x32K sockets, where 2x32K are switchable
At 16K sockets the Pin 27 connected to VCC (Pin 28). Modify to 32K need to cut this and connect Pin 27 to A14 address line. This is very common modification for the two sockets cartridges. Also need to modify the address decoding on cartridge, remove the jumper and connect the A15 to the decoder IC (74ALS138) input.
The next big evolution step when the 27512 (64K) chips are arrived at the end of '80 years.

We started using at the one socket type cartridges, the modification are easy: remove VCC from Pin 1 and connect to A15.
Because also 64K address space decoded for the onboard EXOS ROM I do same trick in the motherboard and started the EXOS 2.2, 2.3 evolution.
The original EXOS 2.0,2.1 only search ROM at the 10h,20h,30h,etc segments, but my updated versions search all segments. Then possible using 64K EPROMs on expansion cards, with more programs in one EPROM. The trick is same: connect Pin 1 to A15. MICROTEAM type cards now can be used with 3x64K ROMs.
There is a pinout summary from 2716 to 27512:

At the '90 years arrived the 128K, 256K EPROMs, these need a more address lines, then got a 32 pins package.

At the cartridge or motherboard only 64K address space decoded, but on EXDOS cards 256K decoded for sockets. Then possible to use this bigger EPROMs. Firstly need modified up to 64K socket.
Adding 27C010 are easy, because the Pin 30 not used which are the Pin 28=VCC in the socket, Connect the EPROM Pin 30 to Pin 32 then the IC have a power. And connect EPROM Pin 2 to A16.
I do this for example on Gflorez card.
27C020 need a A17 at Pin 30 then the previously VCC trick not working, need a separate VCC wire for Pin 32. And bend up the Pin 30 for don't connect with the socket Pin 28, and connect to A17. And Pin 2 to A16 as the 27C010.