rtd DM5816, User Manual

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DM5816/DM6816 RTD Embedded Technologies, Inc.
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P13 — Not Used
This header connector is not used on the DM5816 and should have no jumpers installed.
P14 — Interrupt Source Select
(Factory Setting: OT2)
This header connector, shown in Figure 1-6, lets you select one of four interrupt sources for interrupt
generation. The four sources are: EI1, external interrupt 1, P2-2); EI2, external interrupt 2, P3-2; OT1, the
output of timer/ counter 1; and OT2, the output of timer/counter 2. To connect an interrupt source, place
the jumper across the desired set of pins.
Fig. 1-6 – Interrupt Source Select Jumper, P1
S1 — Base Address
(Factory Setting: 300 hex (768 decimal))
One of the most common causes of failure when you are first trying your module is address contention.
Some of your computer’s I/O space is already occupied by internal I/O and other peripherals. When the
module attempts to use I/O address locations already used by another device, contention results and the
module does not work.
To avoid this problem, the DM5816 has an easily accessible DIP switch, S1, which lets you select any
one of 6 starting addresses in the computer’s I/O. Should the factory setting of 300 hex (768 decimal) be
unsuitable for your system, you can select a different base address simply by setting the switches to any
one of the values listed in Table 1-2. The table shows the switch settings and their corresponding
decimal and hexadecimal (in parentheses) values. Make sure that you verify the order of the switch
numbers on the switch (1 through 4) before setting them. When the switches are pulled forward, they are
OPEN, or set to logic 1, as labeled on the DIP switch package. When you set the base address for your
module, record the value in the table inside the back cover. Figure 1-7 shows the DIP switch set for a
base address of 300 hex (768 decimal).