Quote from: Doug Bissett on February 08, 2014, 08:58:42 pm
I just tried OS/4 on my Lenovo ThinkPad T510. This thing is a little different than the L530:
It does not have a real COM port (it does have a software modem), but it hangs after the first "Loading" line, if I don't enable the debug port.
Hm? Can you, please, describe more precisely? I think I didn't understand that much.
So, it hangs just after you select the kernel in the loader, and it does work if you comment out the dbport statement in os2ldr.ini, doesn't it?
What's with the software modem? Is it, urgh, connected to the COM port?
It seemed a little strange to me too. The section of the OS4 OS2LDR.INI file in question is:
; Debug port
; com port address
; no debug output if statment is omited (but log still accessible
; through copy from oemhlp$ - see below)
dbport=0x3f8
;dbport=0xEC00
If I leave it as it is, I don't have a problem. If I put a semi-colon in front of "dbport=0x3f8", the system simply stops at the first "Loading" line. The machine is not frozen, a Ctrl-Alt-Del causes a reboot. One odd thing is that if I use the QSINIT loader, without even having that line in the INI file, it does not hang. I should note, that I amusing os4krnlr when it hangs.
I think I know what is happening though. The T510 has a feature called "IntelĀ® Active Management Technology" (AMT). Part of that is a device that does "Serial over LAN" (SOL). From what I found out, the device is a serial port (as seen by the computer), but the communication path is redirected over the LAN interface as a TELNET terminal. Apparently, the OS4 loader is detecting that as a serial port, and is getting upset when it isn't told about it. There is some setup in the BIOS for SOL, but I am not sure what it actually does. Someday, I will play with it.
What's with the software modem? Is it, urgh, connected to the COM port?
No, it isn't. It is what we commonly call a "Winmodem". It does not use a normal serial port.
prevents you from the necessity to have two different CONFIG.SYS files.
Actually, the feature to be able to define a different CONFIG.SYS file is an interesting concept, and it works very well. I made one called CONFIG.os4 to use when testing OS/4. I may build a few more, for various reasons.
I'll consider making somewhat a FAQ.
After I learn more about all of this, I may contribute to that, but I am not ready yet.