Understanding the difference between MESA Firmware

On the website store.mesanet.com/ for mesa cards, there section: download support software that looks like different firmware version. 
But there is no documentation on what the difference is between the various or what they are for.

I have tried to google it but come up empty handed. Does anyone know where to get a breakdown of the various firmware version.  
For example, for my card 7i96s there are all these, my guess from the file names is that some seem to be related to adding a daughter board, but what else does it configure and how does it change the functionality of the board.  

7i96sd_esdid
7i96sd_pkt
7i96sd_pktv2
7i96s_16m_fallback
7i96s_2pwmd
7i96s_3pwmd
7i96s_5abobd
7i96s_7i74d
7i96s_7i76d
7i96s_7i77d
7i96s_7i78d
7i96s_7i85d
7i96s_7i85dsdi
7i96s_7i85sd
7i96s_7i89d
7i96s_d
7i96s_dpl
7i96s_dt
7i96s_g540d
7i96s_g540dpl
7i96s_pmd
 

Most names have a daughter card name for devices connected to the 7i96S's
parallel expansion connector (7I85, 5ABOB, G540 etc)

Names with "pl" are for plasma setups
Names with 'sdi" have step/dir index pins for homing to index with step/dir hardware
Names with "pwm" typically replace some step/dir outputs with pwm/dir
Names with "pm" have period measurement hardware
Name with "os" have one-shot firmware
Names with "pkt" have PktUART firmware for things like MODBUS

The final reference for all firmware however, is the .pin file
This text file shows the exact pinout of each corresponding
firmware file (.bin files for the 7I96S)