rtd cpuModule CMX47786HX, User Manual

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CMX47786HX RTD Embedded Technologies, Inc.
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Advanced Digital I/O Ports (aDIO)
This board supports 16 bits of TTL/CMOS compatible digital I/O (TTL signalling) plus two strobe
inputs. Use the BIOS setup to set the multiPort into its aDIO mode. These I/O lines are grouped
into two ports, port 0 and port 1. Port 0 is bit direction programmable and Port 1 is byte program-
mable. Port 0 supports RTD’s two Advanced Digital Interrupt modes, ADI. The two modes are
match and event. Match mode generates an interrupt when an eight bit pattern is received in parallel
that matches the match mask register. The second ADI mode generates an interrupt when a change
occurs on any bit. In either mode masking can be used to monitor selected lines.
When the CPU boots all digital I/O line are programmed as inputs. What this condition means is the
digital I/O line’s initial state is undetermined. If the digital I/O lines must power up to a known state
an external 10 K Ohm resistor must be added to pull the line high or low. Additionally, when the
CPU boots up interrupts 5, 7, 10, 11, and 12 are masked off.
Setup Register Descriptions
The aDIO has a Setup Register and four Runtime Registers. The Setup Register is set by the BIOS,
and can be adjusted by entering the BIOS Setup Utility, and going to Integrated Peripherals. See
Configuring with the RTD Enhanced Award BIOS on page 56 for more details. The Setup Register
may also be read by the driver to determine the base address and interrupt of the aDIO.
aDIO/Watchdog Setup Register (I/O Port 0x1F)
aDIO_Base[2:0] Selects the base address for aDIO and the Watchdog Timer based on the following ta-
ble:
aDIO/WDT_Setup
D7 D6 D4 D3 D2 D0
Reserved aDIO_Base Reserved aDIO_Irq
r r/w r/w r/w
0 0 set by BIOS 0
aDIO_Base[2:0] aDIO Base
I/O Address
Watchdog Timer Runtime
Register I/O Address
000 0x450 0x454
001 0x440 0x444
010 0x410 0x414
011 0x400 0x404
100 0x350 0x354
101 0x340 0x344
110 0x310 0x314
111 0x300 0x304