Spi Connector (St7) - PEP Modular Computers Modular Computers RS485 User Manual

SMART I/O User's Manual
The full-duplex description may be found in the SMART-I/O Advanced
User's Guide.
There is no internal line termination as laid down in DIN 19245 Part 1
and must be performed externally.
The line termination is achieved as shown in
the figure. Assuming a power supply voltage
of +5V emanating from the PROFIBUS
connector (pin 6), the following resistor
values are recommended.
R 150 2%, min 0.25W
t
R 390 2%, min 0.25W
U
R 390 2%, min 0.25W
d

2.5.7 SPI Connector (ST7)

The SPI connector is a 2x5 standard pinrow connector, located on the right-
hand side of the SMART-BASE to enable easy connection of the SMART-
EXT module using a flat ribbon cable connection.
Pin Nr. Signal
1 System VCC
3 System VCC
5 Serial Ext. Select
7 System GND
9 System GND
Page 2 - 16
Note
Pin Nr. Signal
2 Serial RxD
4 Serial TxD
6 Serial CLK
8 Reset
Serial Ext. Interrupt
10
(Controller I/O IRQ4)
©1996 PEP Modular Computers GmbH
Chapter 2 SMART-BASE
Aux. +5V, 90mA
T/RxD +
T/RxD -
Aux. GND
Pin 1
Pin 9
SMART-BASE
R = 390
u
R = 150
t
R = 390
d
ST7
Pin 2
Pin 10
March 12, 1996