Yes on a modern computer you will need a USB to 9 pin RS232 converter or previously use the LPT parallel port.
COM1-IRQ 4, memory addresses 03F8-03FF COM2-IRQ 3, memory addresses 02F8-02FF COM3-IRQ 4, memory addresses 03E8-03EF COM4-IRQ 3, memory addresses 02E8-02EF pg. 396
The "com" ports are computer, serical communications ports (normally RS-232).
The port that is connected can either be COM1 or COM2 depending on the communication port.
COM2 typically uses IRQ 3. The Interrupt Request (IRQ) is a signal used by hardware devices to get the attention of the CPU. In the case of COM2, which is a communication port, it uses IRQ 3 to communicate with the CPU for data transmission and reception.
Pins 1 through 9 on Dell's 12(-1)pin header are numbered identical to a DE-9 serial port, with additional pins 11 & 12 acting as an "enable" or "present" signal to the BIOS for the additional com port. Pin 10 in missing. [2]RxD-[4]DTR--[6]DSR-[8]DCD-[10]nc-[12]{ENABLE} -*--------*--------*--------*--------X--------*- -*--------*--------*--------*--------*--------*- [1]DCD-[3]RxD-[5]GND-[7]RTS-[9]RI-[11]{GND} Pins 11 & 12 need to be tied together to enable COM2. Now, when you reboot & enter BIOS Setup, you will find settings options for two(2) comports instead of just one.
com1,com2 com3
COM1 and COM2 originally referred to the serial port interfaces on a PC. Now they can refer to any port, virtual or physical.
well COM1, COM2, COM3, and COM4 are sometimes configured as Serial Ports.
COM2 and COM4 use the same interrupt by default (IRQ3). The same is also true for COM1 and COM3 (IRQ4).
The serial ports are named ttyS0, ttyS1, etc.And usually correspond respectively to COM1, COM2, etc. in DOS/Windows
COM1-IRQ 4, memory addresses 03F8-03FF COM2-IRQ 3, memory addresses 02F8-02FF COM3-IRQ 4, memory addresses 03E8-03EF COM4-IRQ 3, memory addresses 02E8-02EF pg. 396
The "com" ports are computer, serical communications ports (normally RS-232).
MODE LPTx=COMx Unfortunately MODE LPTx:=COMx redirects parallel printer output to a COMport, I've never seen any indication that it will work the other way. For example, to accommodate a 1200 baud serial printer on COM2 to a program that only has LPT1 output: MODE COM2:1200,n,8,1,p sets up the comport with continuous retry MODE LPT1:=COM2 redirects LPT1 output to COM2
There generally r 2 com ports, com1 and com2. They are RS232 ports which r serial ports.one way to communicate between 2 PCs is to use a software called hyperterminal..its there in evry computer.( accessories-> communication tools). if not u can also install it. u can find more information on it online..in case..1> u can either use an RS232 to IR converter device connected to the respective ports of both the comps to communicate.u'l be usin IR communication in dis case.2> u can connect a cable between these two ports of both the comps( female-female...as RS232 is a male port).but ure comps wud need to b in close proximity for a physical connection like dis. u can get back to me for any further clarification on the same.
There's no limit to the number of serial ports. The maximum number for the traditional ports is 2 (COM1/COM3 and COM2/COM4). Plus you can attach additional serial port adapters to a USB port, up to 127 per controller.
IRQ 3 is for COM2 and COM4 (serial ports). See related link.
If your system only has one COM: port, you will have to physically add in a card or USB-RS232 serial adapter, and follow the installation instructions. If your system has 2 COM: ports, make sure that in the CMOS (BIOS) settings, that the port isn't disabled or assigned as an InfraRed port. Also, make sure that you physically have the connectors at the back of the unit available. Many motherboards offer COM2: only as an option, and it requires an optional (not included) cable that hooks to the motherboard.