Diff: SPISlave.h

Revision:

20:029aa53d7323

Child:

27:7110ebee3484

diff -r e6be4cd80aad -r 029aa53d7323 SPISlave.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SPISlave.h	Thu Jun 03 11:17:50 2010 +0000
@@ -0,0 +1,122 @@
+/* mbed Microcontroller Library - SPI
+ * Copyright (c) 2010 ARM Limited. All rights reserved. 
+ * sford
+ */
+
+#ifndef MBED_SPISLAVE_H
+#define MBED_SPISLAVE_H
+
+#include "platform.h"
+#include "PinNames.h"
+#include "PeripheralNames.h"
+#include "Base.h"
+
+namespace mbed {
+
+/* Class: SPISlave
+ *  A SPI slave, used for communicating with a SPI Master device
+ *
+ * The default format is set to 8-bits, mode 0, and a clock frequency of 1MHz
+ *
+ * Example:
+ * > // Reply to a SPI master as slave
+ * >
+ * > #include "mbed.h"
+ * >
+ * > SPISlave device(p5, p6, p7, p8); // mosi, miso, sclk, ssel
+ * >
+ * > int main() {
+ * >     device.reply(0x00);              // Prime SPI with first reply
+ * >     while(1) {
+ * >         if(device.receive()) {
+ * >             int v = device.read();   // Read byte from master
+ * >             v = (v + 1) % 0x100;     // Add one to it, modulo 256
+ * >             device.reply(v);         // Make this the next reply
+ * >         }
+ * >     }
+ * > }
+ */ 
+class SPISlave : public Base {
+
+public:
+
+    /* Constructor: SPI
+     *  Create a SPI slave connected to the specified pins
+     *
+     * Variables:
+     *  mosi - SPI Master Out, Slave In pin
+     *  miso - SPI Master In, Slave Out pin
+     *  sclk - SPI Clock pin
+     *  ssel - SPI chip select pin
+     *  name - (optional) A string to identify the object     
+     *
+     * Pin Options:
+     *  (5, 6, 7i, 8) or (11, 12, 13, 14)
+     *
+     *  mosi or miso can be specfied as NC if not used
+     */
+    SPISlave(PinName mosi, PinName miso, PinName sclk, PinName ssel,
+        const char *name = NULL);
+
+    /* Function: format
+     *  Configure the data transmission format
+     *
+     * Variables:
+     *  bits - Number of bits per SPI frame (4 - 16)
+     *  mode - Clock polarity and phase mode (0 - 3)
+     *
+     * > mode | POL PHA 
+     * > -----+--------	 
+     * >   0  |  0   0 
+     * >   1  |  0   1
+     * >   2  |  1   0 
+     * >   3  |  1   1
+     */
+    void format(int bits, int mode = 0);
+
+    /* Function: frequency
+     *  Set the spi bus clock frequency
+     *
+     * Variables:
+     *  hz - SCLK frequency in hz (default = 1MHz)
+     */
+    void frequency(int hz = 1000000);
+
+    /* Function: receive
+     *  Polls the SPI to see if data has been received
+     *
+     * Variables:
+     *  returns - zero if no data, 1 otherwise
+     */
+    int receive(void);
+
+    /* Function: read
+     *  Retrieve  data from receive buffer as slave
+     *
+     * Variables:
+     *  returns - the data in the receive buffer
+     */
+    int read(void);
+
+    /* Function: reply
+     *  Fill the transmission buffer with the value to be written out
+     *  as slave on the next received message from the master.
+     *
+     * Variables:
+     *  value - the data to be transmitted next
+     */
+    void reply(int value);
+
+protected:
+
+	SPIName _spi;
+	
+    int _bits;
+    int _mode;
+    int _hz;
+
+};
+
+} // namespace mbed
+
+#endif