Datasheet for a NEC Chip in DEC Professional 350

[Rob Jarratt]

I have posted previously about a DEC Pro 350 I am trying to get working
again. At the moment it seems to be constantly resetting the CPU.

 

I have traced one possible path for the cause of this back to a NEC chip for
which I cannot find a datasheet. It is a 40-pin DIP it is marked "NEC Japan
8239K6 D7201C". All I have been able to find is more modern USB host
controllers.

 

Can anyone tell me what it is? It is marked E32 (on the left about half way
up) in this picture:
https://rjarratt.files.wordpress.com/2018/10/system-board-labelled.jpg

 

Thanks

 

Rob