SieMo S50037 Data Book PRELIMINARILY

Multi-Slave Operation

SieMo should not be connected in a multi-slave arrangement by simple parallel connection of slave MISO lines. When SieMo is deselected (SPI_CSB = 1), the SPI_MISO line does not float. Instead, SieMo outputs 0 if the processor is running or 1 if it is stopped.

Writing to SieMo

To write to the SieMo, the 8-bit write command (00000010) is sent first (C[7:0] followed by a 16-bit address (A[15:0]). 16 bits of data (D:[15:0]) are sent.

Terminal

Type

Description

Device

PC Parallel

 

 

 

Terminal

Connector

SPI_CSB

CMOS input

Serial Peripheral Interface Chip

E1

2

 

 

Select

 

 

SPI_CLK

CMOS input

Serial Peripheral Interface SPI

E2

9

 

 

Clock

 

 

SPI_MOSI

CMOS input

Serial Peripheral Interface SPI

E3

8

 

 

Data Input

 

 

SPI_MISO

CMOS output

Serial Peripheral Interface SPI

E4

10

 

 

Data Output

 

 

GND

 

 

B3

19

SPI Timing

figure 22 SPI write operation a

figure 23 SPI write operation b

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Siemens S50037 Multi-Slave Operation, Writing to SieMo, SPI Timing, Terminal Type Description Device PC Parallel Connector