Thread: IBM Model 50
View Single Post
Old 25th Apr 2018, 9:52 pm   #7
arjoll
Dekatron
 
arjoll's Avatar
 
Join Date: May 2006
Location: Invercargill, New Zealand
Posts: 3,440
Default Re: IBM Model 50

Quote:
Originally Posted by TonyDuell View Post
I think what has happened is that the battery that supplies the CMOS RAM containing the configuration information (what disk drives it has, etc) has gone flat. Or at least that configuration data is lost. As a result, it can't find the hard disk to boot from and is going into ROM BASIC (genuine IBM PC family machines, starting with the original 5150 have Microsoft BASIC in ROM).
Just jumping in here to clarify something - the 5150 PC and 5160 PC/XT do not have the configuration saved in NVRAM like later machines. That only came in with the 5170 PC/AT.
arjoll is offline