Article # 222, added by Geoworks, historical record
| first |
previous |
index |
next |
last |
Serial ports, detecting and specifying in GEOS.INI.
DETECTING PORTS --------------- GEOS determines which ports are available by checking the memory locations 40:0 through 40:F. Before running GEOS, you can use debug (or sid, if you're a DR DOS user) to see which ports are enabled. If any of the four COM port locations contain zeros, then that's as far as GEOS will go. The same information should be in your SYSINFO file, too. Here's an example: Bios data area (0040h:0): 0000: f8 03 f8 02 e8 02 00 00 78 03 00 00 00 00 00 00 F8 03 means COM 1 is active and available. F8 02 is COM 2 E8 02 is COM 4 E8 03 would be COM 3 if it were there. If it looks like this: Bios data area (0040h:0): 0000: f8 03 f8 02 00 00 e8 02 78 03 00 00 00 00 00 00 then GEOS will never see COM4. If it looks like this: Bios data area (0040h:0): 0000: f8 03 f8 02 e8 03 e8 02 78 03 00 00 00 00 00 00 then it means you have all four COM ports available (and 78 03 is your first parallel port). Keep in mind that SYSINFO is only created when you first install GEOS, so if things have changed in your hardware since you originally installed GEOS, then you might not have current information in SYSINFO. Using debug or sid will display things as they are now. To use debug or sid, enter DEBUG or SID at the DOS prompt, then enter d 40:0 at the debug or sid prompt. then enter q to quit. You can also use debug or sid to poke values into those locations and force GEOS to see ports that don't really exist. INSTALLING GEOS PORT PROBLEMS ----------------------------- Symptom: After running textual setup, the screen turns gray, then GEOS locks up. Cause: When graphical setup starts, it loads the serial driver which tries to figure out which COM ports exists and what their interrupt levels are. This problem can happen if the user has any COM ports set to non-standard interrupt levels. The standard interrupt levels are: COM1 = 4 COM2 = 3 COM3 = 4 COM4 = 3 The interrupt levels are set by DIP switches or jumpers on serial port cards and modems cards. Some cards don't allow changing the interrupt levels from the standard 4 (for COM1) and 3 (for COM2). Work around: Add entries to the GEOS.INI file for each of the COM ports. The entries are of the form 'portX = Y' (where X is the COM port number and Y is that port's interrupt level) in the [serial] section. For example: [serial] port1 = 4 port2 = 3 port3 = 5 port4 = 2 If a COM port doesn't exist, its entry can be omitted.