IBM 5170 - Clearing Part of the CMOS/RTC RAM for GSETUP
A design flaw in GSETUP is that it expects the existing expansion memory setting in the CMOS/RTC chip to be 0 or a multiple of 128 KB.
Sometimes, in the IBM 5170, the existing expansion memory setting will not be 0 nor a multiple of 128 KB (because the RAM in the CMOS/RTC chip won't be entirely zeroed).
The following procedure will clear (zero) some of the settings in the 5170's CMOS/RTC RAM, one being the expansion memory setting.
1. Remove any floppy/diskette that is in drive A:
2. Power on the IBM 5170.
3. At the (RESUME = "F1" KEY) prompt, press the [F1] key. The IBM 5170 will boot into Cassette BASIC.
4. Enter the following line:
for x = 14 to 45: out 112,x: out 113,0: next
5. Power off the 5170.