Just like no one thought you could mine equihash or litecoin with an asic and now it can be done.
Only fools thought it would be impossible. Anybody with a clue knew that it would just take time for the chip dev ROI to make sense.
And yes you could mine equihash with a microcontroller type device if coded correctly don't know how much speed you can get but it could be done.
You would still need the DRAM the algorithm requires, which is unlikely to even be addressable on a MCU.
Where as with the antminers you have a whole OS to work with. Who says you have to use cgminer, a replacement custom software could be placed on the miner instead. Basically you would turn another miner into a emulator of other miners.
Custom replacement software won't make a difference, because all the mining software is doing is sending jobs to the ASIC boards and receiving valid nonces back.
Currently I am mining bitcoin and equihash from a the same Z9. By merging different parts of each OS/Firmware I have 1 hashboard from a V9 running with 3 hashboards of the Z9. I just started this last night but so far it has been running fine. I have 2 different weg gui's to access and monitor each type of board. I get 1.5-2.0 TH from the bitcoin board.
If it continues to work well I may release a version so people can make a few bits of bitcoin while they are mining equihash by just adding a V9 hashboard to the 4th plug on the main miner controller. I have 4 boards on another Z9 and it is pulling 74-80 k/sol @ 656 mhz
This is completely different from what you insinuated earlier, and would work perfectly fine, of course. The ASIC boards simply interface over serial ports, this much is universal to miners even from other vendors. There is a caveat preventing mixing and matching hashboards on Bitmain devices natively though, it would require new driver code for cgminer as Bitmain hardcodes most of their changes to be device-specific. If you run two copies of cgminer, as it sounds like you're doing, it should operate fine - although I don't know why you'd ever want to run a V9 hashboard unless you had free power. Even then, it's mighty slow.