Mikroelektronika MIKROE-724 データシート

mikroBasic PRO for dsPIC30/33 and PIC24

MikroElektronika

473

SPI_Set_Active

sub procedure SPI_Set_Active(dim read_ptr as ^TSpi_Rd_Ptr, dim write_ptr as 

^TSpi_Wr_Ptr)

Description Sets the active SPI module which will be used by the SPIx_Read and SPIx_Write routines.
Parameters Parameters:

- 

read_ptr

: SPI1_Read handler 

- 

write_ptr

: SPI1_Write handler 

Nothing.

Routine is available only for MCUs with multiple SPI modules.

Used  SPI  module  must  be  initialized  before  using  this  function.  See  the  SPIx_Init  and  SPIx_Init_

Advanced routines.

SPI_Set_Active(@SPI1_Read, @SPI1_Write) ‘ Sets the SPI1 module active

Number of SPI modules per MCU differs from chip to chip. Please, read the appropriate datasheet 

before utilizing this library.

Library Example

The code demonstrates how to use SPI library functions for communication between SPI2 module of the MCU and 

MCP4921 DAC chip.

Copy Code To Clipboard 

program SPI

dim Chip_Select as sbit at LATF0_bit

    Chip_Select_Direction as sbit at TRISF0_bit

dim value as word

sub procedure InitMain()

  TRISB0_bit = 1                           ‘ Set RB0 pin as input

  TRISB1_bit = 1                           ‘ Set RB1 pin as input

  Chip_Select = 1                          ‘ Deselect DAC

  Chip_Select_Direction = 0                ‘ Set CS# pin as Output

  SPI1_Init()                              ‘ Initialize SPI module

sub procedure DAC_Output(dim valueDAC as word)

dim temp as byte

  Chip_Select = 0                          ‘ Select DAC chip

 

  temp = word(valueDAC >> 8) and 0x0F      ‘ Store valueDAC[11..8] to temp[3..0]

  temp = temp or 0x30                      ‘ Define DAC setting, see MCP4921 datasheet