Black Box RS-232, IC181C manual 4. E5, sharing multiple serial interface cards, Option Selection

CHAPTER 4: Option Selection

Set jumper to “S” if you are using more than one Four Port RS-232 Serial Interface in a bus or you wish to remove the pull-down resistor completely for hardware compatibility.

NOTE

Setting the board in this configuration when it is not accompanied by a pull-down resistor will prevent the ports from triggering an interrupt. The factory default for this board is COM1: and COM3: sharing IRQ4, and COM2: and COM4: sharing IRQ3.

1 2

M

S

N

M

S

N

3 4

Figure 4- 4. E5, sharing multiple serial interface cards.

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