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Wires No More!
$159.99 a pair
Wireless Serial Adapter
(Bluetooth to RS232)
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Card Configuration
Jumper settings should be set based on the following descriptions. Refer to Figure 5
for the location of jumpers on the multiport card.
Figure 1(JP1, JP2, JP3, JP4)
JP1, JP2, JP3, and JP4
are used to set the port address of each UART.
- EN must be open to enable the port. If the jumper is on, then the port
is disabled.
- A9 through A3 is used to select the address of the
port. They represent the upper 7 bits of the address. A2 through A0
are zero and require no jumpers. Jumper on(shorted) represents a logical zero. Jumper
off(open) represents a logical one. Following is an example of how the addresses are
computed.
Figure 1 is configured for address 2A0 hexadecimal. It was computed as
follows.
Convert to binary
HEX 2 A 0
Binary 0010 1010 0000
Get rid of the lower three bits and the upper 2 bits. This leaves only A9 through
A3.
Noting that the jumper should be opened(no jumper) for a logical one, and closed for a
logical zero(jumpered) the jumper settings should be:
Jumper must be on (shorted) for A8, A6, A4,
& A3
Jumper must be off(opened) for A9, A7, A5
Figure 2(JP6)
JP6 selects the interrupt that each port will use. Note that any port
can use any interrupt. Some or all may be shared. Figure 2 shows all
ports using IRQ 5.
Figure 3(JP5)
JP5 selects the interrupt status register address. The interrupt
status register is an 8 bit register that may be used to determine which port on the card
is generating an interrupt. The format is as follows:
Bit 0 Port 1
Bit 1 Port 2
Bit 2 Port 3
Bit 3 Port 4
Bit 4 to Bit 7 Unused
- EN must be closed to enable the port. If the jumper is on, then the
port is enabled.
- A9 through A0 is used to select the address of the
port. Jumper on(shorted) represents a logical zero. Jumper off(open) represents a logical
one. Following is an example of how the addresses are computed.
Figure 3 is configured to address 2BF hexadecimal. It was computed as
follows.
Convert to binary
HEX 2 B F
Binary 0010 1011 1111
Get rid of the upper 2 bits. This leaves only A9 through A0.
1010111111
Noting that the jumper should be opened(no jumper) for a logical one, and closed for a
logical zero(jumpered) the jumper settings should be:
Jumper must be on(shorted) for A8, A6
Jumper must be off(opened) for A9, A7, A5,
A4, A3, A2, A1, & A0
Figure 4(JP7)
JP7 is used to enable interrupts. Figure 4 was
configured to enable only IRQ 5. A jumper should be placed on every interrupt that is
selected in JP5. In other words if IRQ 5 and IRQ 10 were selected for
different ports, then a jumper must be placed on 5 and 10 above.
JP8 is used to select wait states. It selects from 1 to 4 wait states.
JP9 should be left opened to ensure that when an interrupt occurs, it
is indicated by a logical zero in the interrupt status register.
Figure 5
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