Differences

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--- en:netzer:spi-master [2015/12/23 17:10]
svesch [Communication]
+++ en:netzer:spi-master [2015/12/23 17:37]
svesch [SPI master in single slave operation]
@@ Line 123: / Line 123: @@
 | T | 0x54 | Wait 1\ ms till processing of the next character. | 1.5 |
 | All others | Character is transparently transmitted. |
+===== SPI master in single slave operation =====
+For using this SPI master in a single slave environment this example is provided here.
+We assume that the slave is connected with the SPI_CS wire like shown below.
+{{:en:netzer:spi_master_connection.gif|}}
+The SPI_CS shall be low active - a low level selects the slave.
+The pull up resistor at CS is needed to prevent false selection.
+This may occur on power up if CS is not driven by Netzer.
+The pull up resistor at SPI_MI is needed to prevent floating in case the slave is not selected and therefore the pin is not driven.
+The data string <code>01 23 45 67 89</code> shall be sent to the SPI slave.
+The command for controlling the SPI_CS line is an escape sequence consisting of two bytes:
+<code>5c 69</code> for setting SPI_CS to low and
+<code>5c 49</code> for setting SPI_CS to high.
+The final code together:
+<code>5c 69 01 23 45 67 89 5c 49</code>

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