DIGITAL-LOGIC SM800/900DK, Technical User'S Manual

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DIGITAL-LOGIC AG
SM800/900DK Technical Manual V1.2B
83
13.7.4. Serial COM1/2 Interface
The sm800/900PCX provides the TTL serial signals. The RS232-converter is not integrated.
Use a MAX211, or similar converter, for V24/RS232C interfaces.
Use 4x470nF as pump-capacitors for the MAX211.
100nF are not enough over the extended temperature range.
If the serial interfaces are unused, all inputs must be 1K Ω pulled-up.
If the inputs are left open, some operating systems will not boot or will fail.
All serial data lines must be EMI filtered directly at the connector. Use 47pF to earth.
13.7.5. Parallel Interface
The sm800/900PCX provides the TTL parallel signals.
All parallel data lines and control lines must be EMI filtered directly at the connector.
Use 47pF to earth.
There is no problem if the parallel interface is unused; leave the pins open.
13.7.6. Floppy Interface
The sm800/900PCX provides the TTL floppy signals.
There is no problem if the floppy interface is unused; leave the pins open.
13.7.7. PS/2-Keyboard/Mouse Interface
The sm800/900PCX provides the TTL PS/2 signals.
All PS/2 signals are pulled up with 1k to +5Volt on the smartModule.
There is no problem if the PS/2 interface is unused; leave the pins open.
All PS/2 data lines and power lines must be EMI filtered directly at the connector. Use 47pF to earth.
13.7.8. VGA Interface
The sm800/900PCX provides the TTL (V/H-Synch) / Analog signals.
All Analog-Color-VGA signals are terminated with 75 Ohms on the smartModule.
There is no problem if the VGA interface is unused; leave the pins open.
All VGA data lines, synch lines and power lines must be EMI filtered directly at the connector.
Use 47pF to earth.
Use 33 Ohms as series resistor. Implement an overvoltage protection on the synch lines and on the
analog (color) lines.
DDCADATA and DDCACLK are 3.3V I/O buffers connecting the GMCH to the monitor. If higher signaling
voltage (5V) is required by the monitor, level shifting devices may be used. Pull-up resistors of 2.2k (or of the
appropriate value derived from simulation) are required on each of these signals.