Diff: src/spi.cpp

Revision:

14:46aad38346a6

Parent:

13:c446482b0360

Child:

15:fd2c3c3038bf

--- a/src/spi.cpp	Fri Aug 14 14:26:41 2020 +0530
+++ b/src/spi.cpp	Fri Oct 16 21:23:58 2020 +0530
@@ -25,11 +25,14 @@
 /********************** Macros and Constants Definitions **********************/
 /******************************************************************************/
 
+#define		SPI_16_BIT_FRAME		16		// SPI 16-bit frame size
+#define		SPI_8_BIT_FRAME			8		// SPI 8-bit frame size
+
 /******************************************************************************/
 /********************** Variables and User defined data types *****************/
 /******************************************************************************/
 
-static uint8_t spi_format_bytes = 16; 	// SPI format
+static uint8_t spi_format_bytes = SPI_16_BIT_FRAME;   	// SPI format
 
 /******************************************************************************/
 /************************ Functions Declarations ******************************/
@@ -97,10 +100,10 @@
 		    SPI frequency is required, consult your device documentation.
 		  **/
 		spi->frequency(param->max_speed_hz);
-		spi->format(16, param->mode);              // 16-bit data write/read format
-		spi_format_bytes = 16;
-		spi->set_default_write_value(0x00);        // code to write when reading back
-		ss->write(GPIO_HIGH);                      // set SS high
+		spi->format(SPI_16_BIT_FRAME, param->mode);  // data write/read format
+		spi_format_bytes = SPI_16_BIT_FRAME;
+		spi->set_default_write_value(0x00);          // code to write when reading back
+		ss->write(GPIO_HIGH);                        // set SS high
 
 		return SUCCESS;
 	}
@@ -155,9 +158,10 @@
 {
 	mbed::SPI *spi; 			// pointer to new spi instance
 	mbed::DigitalOut *ss;  		// pointer to new SS instance
-	uint8_t num_of_words;		// Number of words in SPI frame
-	uint16_t rw_data;			// SPI read data
-	uint8_t data_index = 0;		// Data index
+	uint16_t num_of_words;		// Number of words in SPI frame
+	uint16_t rw_data;			// SPI read data (16-bit)
+	uint16_t data_index = 0;	// Data index
+	size_t byte;				// Byte read/write index
 
 	if (desc) {
 		spi = (SPI *)(((mbed_spi_desc *)(desc->extra))->spi_port);
@@ -168,14 +172,14 @@
 
 		/* Determine the data transmit/receive format based on parity of data */
 		if (!(bytes_number % 2)) {
-			if (spi_format_bytes != 16) {
-				spi->format(16, desc->mode);
-				spi_format_bytes = 16;
+			if (spi_format_bytes != SPI_16_BIT_FRAME) {
+				spi->format(SPI_16_BIT_FRAME, desc->mode);
+				spi_format_bytes = SPI_16_BIT_FRAME;
 			}
 		} else {
-			if (spi_format_bytes != 8) {
-				spi->format(8, desc->mode);
-				spi_format_bytes = 8;
+			if (spi_format_bytes != SPI_8_BIT_FRAME) {
+				spi->format(SPI_8_BIT_FRAME, desc->mode);
+				spi_format_bytes = SPI_8_BIT_FRAME;
 			}
 		}
 
@@ -204,7 +208,7 @@
 				num_of_words--;
 			}
 		} else {
-			for (size_t byte = 0; byte < bytes_number; byte++) {
+			for (byte = 0; byte < bytes_number; byte++) {
 				data[byte] =  spi->write(data[byte]);
 			}
 		}