Hello to all IBM 5100 owners, I have started disassembling and commenting the Executable ROS of the 5100 that a kind soul has exctracted and provided me with the dump. I've come across an inconsistency with the Maintenance Information Manual as found on the net. I have both SY31-0405-2 and SY31-0405-3. The issue is the description of the control I/O commands for device 1 (non-executable ROS selects). The manual says bit 12 is APL select and bit 13 is BASIC/Common select (page C-4), and that matches the block diagram on page 5-20. But in fact, the code uses the bits as defined for the 5110 (12=select BASIC, 13=select APL, 14=select Common) and therefore, the 5100 must be different from the system described in the MIMs. So here are two questions: - Does someone have a newer version of the MIM, i.e. SY31-0405-4 or greater? A scan would be wonderful, especially because the scans for the available MIMs are horrible... - Are there known major revision changes in the 5100 line? Christian PS: I really mean 5100, not 5110 or 5120 ;-)