LisaList2

General Category => LisaList2 => Topic started by: ried on October 16, 2025, 10:01:13 pm

Title: Lisa 1 to 2 upgrade instructions addendum
Post by: ried on October 16, 2025, 10:01:13 pm

Here's a copy of the Level 1 Lisa Technical Procedures #072-0085 manual dated September, 1984. There's an interesting loose page floating in the back, which provides an update on the Lisa 1 to 2 upgrade procedure.

First, the CPU ROMs were no longer included in the upgrade kit. This is surprising, because I thought some later versions of LOS were not supported by C or D ROMs.

Second, installers are instructed to remove a second resistor (R41) from the I/O board. Apparently, for some period of time R47 was the only one removed during the upgrade process. That also seems a bit odd.

Title: Re: Lisa 1 to 2 upgrade instructions addendum
Post by: sigma7 on October 16, 2025, 11:05:50 pm

Quote from: ried on October 16, 2025, 10:01:13 pm

Installers are instructed to remove a second resistor (R41) from the I/O board.
Apparently, for some period of time R47 was the only one removed during the upgrade process.

Removing R47 is associated with switching from the Twiggy to 3.5" floppy drive.

Removing R41 was a tweak to address ProFile issues.