Siemens S50037 manual Multi-Slave Operation, Writing to SieMo, SPI Timing

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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