CHAPTER 5
SWITCH SETTING

The nine jumper blocks on the PCCOM ISA bus 4 port adapter must be configured correctly in accordance with the operating system you are using.

JP1 (Jumper 1)
Determines the I/O address of port 1.

JP2 (Jumper 2)
Determines the I/O address of port 2.

JP3 (Jumper 3)
Determines the I/O address of port 3.

JP4 (Jumper 4)
Determines the I/O address of port 4.

JP5 (Jumper 5)
Selects the interrupt vector address and determines which port is active when an interrupt occurs.

JP6 (Jumper 6)
Selects which interrupt will be used in the range IRQ2 through IRQ15.

JP7 (Jumper 7)
Enable selected interrupt. The selection of this jumper should correspond to the selection of JP6.

JP8 (Jumper 8)
Select delay wait state.

JP9  (Jumper 9)
Select the activation status (low or high) of interrupt vector.

It is important to refer to the user manual supplied with your operating system to determine the correct configuration. Although we provide installation advice for various operating systems, it is not possible to cover all systems in this user guide. Please contact your supplier if you have any difficulties with configuration.

IMPORTANT: CARE MUST BE TAKEN IN SELECTING THE CONFIGURATION OF JUMPERS AND SWITCH TO ENSURE YOU DO NOT DUPLICATE SETTINGS OF OTHER EQUIPMENT ALREADY INSTALLED IN YOUR COMPUTER. DUPLICATION OF SETTINGS WILL RESULT IN A MALFUNCTION OF ONE OR BOTH DEVICES.

Please refer to the following settings for each switch and jumper block. If you are installing more than one board, do not duplicate jumper settings for any parameter.

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JP1 to JP4 are used to select UART I/O address for each port. Where JP1 is used to select port 1 address, JP2 is used to select port 2 address etc. Each JP contains A9 to A3 jumper pins and EN jumper pin.  The A9 to A3 are used to set I/O port address, when the corresponding pin is short means 0, otherwise no pin short means 1.  The figure above set the I/O address to 2A0H. The EN pin is used to enable the selected port, not short the jumper means enable the port, otherwise, if you short the jumper means disable this port.

JP5 is used to set the interrupt vector address. A9 to A0 corresponding to address selection bit, not short the pin when the user select the bit to 1, otherwise short the pin to select 0. The default setting of this board is 2BFH. The EN pin is used to enable the interrupt vector, when short the pin means enable, otherwise not short the pin means disable interrupt vector.

The interrupt vector is used to detect which of the four channels is creating the interrupt. After the interrupt vector is enabled, the user may read bit 0 from interrupt vector address to detect whether channel 1 is creating an interrupt or not? To read bit 1 to detect whether channel 2 is creating an interrupt or not? ...  etc. If you set active low (JP9 open), when read a data bit from the interrupt vector is 0, the corresponding channel is creating an interrupt. When the bit content is 1, there is no interrupt.

JP6 is a channel interrupt select matrix, you may select interrupt for each channel. It can arrange these interrupts in any combination, this means it can set all ports in different interrupt, or combine several ports into a group to share the same interrupt. The figures shown above are for CH1 and CH2 to be combined on interrupt 10, CH3 on interrupt 11 and CH4 on interrupt 12.

The default setting of this board is combined to share the same interrupt (IRQ5).

The JP7 is used to enable IRQ2 to IRQ15 bus lines.  Note that the selection of these jumpers should correspond to the selection of the interrupts on the interrupt select matrix (JP6). For example, if you select IRQ5 and IRQ10 on the JP6, you need short IRQ5 and IRQ10 of JP7. However, If more than one boards use common IRQ, only select one board to short the JP7.

If you set active low (JP9 open), when read a data bit from the interrupt vector is 0, the corresponding channel is creating an interrupt. When the content of bit is 1, there is no interrupt.

If you set active high (JP9 short), when read a data bit from the interrupt vector is 1, the corresponding channel is creating an interrupt. When the content of bit is 0, there is no interrup.