Happy 1050 to ED (Vintage computing)

[Tedster]

Does anyone remember why the old "Happied chipped" Atari 1050s stall out when switching over from fast mode to 1050 enhanced density?

 

[Samstoned]

I tried updating uarts and that did not work
no sorry I remember the Intel 8086's we did dos on
optical drives where 3000.00 usd then