SPI made Simple

The SPI Bus (Serial Peripheral Interface) is based on simple shift registers. A detailed description by Martin Schwerdtfeger (MCT GmbH) is available in English www.mct.net/faq/spi.html and in German www.mct.de/faq/spi.html.

SPI made Simple is a modular concept, using the SPI bus to connect various functional blocks. Actually, SPImS is nothing else but the definition of a connector:

DOTW SPImS
Pin Function Function Pin
1
3
5
7
9
11
13
MOSI
MISO
CLK
CS0
CS1
CS2
CS3
GND
GND
GND
5 Volt
5 Volt
nc
IRQ
2
4
6
8
10
12
14

Abbreviations:

MOSI Master Out Slave In
MISO Master In Slave Out
CLK Clock for the shift registers
CS0-CS3 Chip Select
nc free for application-specific use
5 Volt supply voltage (5 Volt DC, stable)
IRQ Interrupt ReQuest

A 14-pin connector with 2.54mm spacing is used. The boards are connected via flat ribbon cables. Wiring MOSI - GND - MISO - GND - CLK - GND etc. guarantees a defined impedance and prevents cross talk.

Currently available products:

Single board computer NET7026
Single board computer NET2106
Base board ULCbaseA
Base board BASE2
Motion controller BRIDGE1
Relay board RELAIS8
128x64 pixel LCD LCD1
Seven-segment display LED7

More boards will follow!

www.mct.net