Driver for CC3000 Wi-Fi module

Dependencies:   NVIC_set_all_priorities

Dependents:   CC3000_Simple_Socket Wi-Go_IOT_Demo

You are viewing an older revision! See the latest version

Homepage

Information

The current code has been reworked to a full object oriented application and contains an mbed socket compatible API.

CC3000 Wi-Fi module library

Info

This is the low level driver for TI's SimpleLink CC3000 device.
Port from Avnet's Wi-Go KEIL code (based on TI's CC3000 code).
Special thanks to Jim Carver from Avnet for providing the Wi-Go board and for his assistance.

Differences with TI's original code

The code functionality stays exactly the same.
In order to make it easier to use the code, following changes were made :

  • Addition of a tool to shift all IRQ priorities to a lower level since it is very important to keep the SPI handler at the highest system priority, the WLAN interrupt the second highest and all other system interrupts at a lower priority, so their handlers can be preempted by the CC3000 interrupts.
  • Addition of low level I/O controls and conditional compiler controls in cc3000_common.h.
  • CC3000 initialisation, pin declarations, SPI and WLAN irq priorities are set in Init_HostDriver , we need to call this function at the start of the main function.
  • The SPI and HCI code are joined into one file.
  • The include list has been rearranged - Only #include "wlan.h" is needed in the user API.
  • Part of the CC3000's user eeprom memory is used to store additional info (52 bytes in NVMEM_USER_FILE_1):
# bytesDescriptionInfo
1First time config parameterUseful when connecting
2PatchProgrammer versionused in the PatchProgrammer code
2Service Pack versionused in the PatchProgrammer code
3Driver Versionused in the PatchProgrammer code
3Firmware Versionused in the PatchProgrammer code
1CIK validation (Client Interface Key)
40CIK data (Client Interface Key)used with the exosite

Using the Library

Warning

Once and a while, this library disables/enables ALL PORTA interrupts.
Keep this in mind when using other interrupts on this port.

There is an option to only disable the CC3000 interrupt
Beware : Even though this works with the PatchProgrammer and the CC3000_Simple_Socket code, it hasn't been tested with any other application. Since this method works differently/slower, the time critical code could easily be compromised, especially when other interrupts are used.
Following changes are needed to try this out:
In cc3000_common.h, replace

#define WLAN_ENABLE_IRQ     NVIC_EnableIRQ(PORTA_IRQn);
#define WLAN_DISABLE_IRQ    NVIC_DisableIRQ(PORTA_IRQn);

with

#define WLAN_ENABLE_IRQ     wlan_int.fall(&WLAN_IRQHandler);
#define WLAN_DISABLE_IRQ    wlan_int.fall(NULL);


In cc3000_spi_hci.cpp - function SpiWrite(), add following code immediately after tSLInformation.WlanInterruptEnable();

// check for a missing interrupt between the CS assertion and interrupt enable
if (tSLInformation.ReadWlanInterruptPin() == 0)
{
    SpiWriteDataSynchronous(sSpiInformation.pTxPacket, sSpiInformation.usTxPacketLength);
    sSpiInformation.ulSpiState = eSPI_STATE_IDLE;
    WLAN_DEASSERT_CS;
}

A user API is needed to access the CC3000 functions.
Examples:

Using the library with other processors

cc3000_common.cpp loads the irq tool for all targets:

#include "NVIC_set_all_priorities.h"

All current mbed targets are supported by this library.

All low level settings that need to change are available in cc3000_common.h

//*****************************************************************************
//              PIN CONTROLS & COMPILE CONTROLS
//*****************************************************************************
// Compiler control
#define CC3000_UNENCRYPTED_SMART_CONFIG   // No encryption
//#define CC3000_TINY_DRIVER                // Driver for small memory model CPUs

//Interrupt controls
#define NVIC_ALL_IRQ        NVIC_set_all_irq_priorities(3);         // Set ALL interrupt priorities to level 3// Set ALL interrupt priorities to level 3
#define NVIC_SPI_IRQ        NVIC_SetPriority(SPI0_IRQn, 0x0);       // Wi-Fi SPI interrupt must be higher priority than SysTick
#define NVIC_PORT_IRQ       NVIC_SetPriority(PORTA_IRQn, 0x1);
#define NVIC_SYSTICK_IRQ    NVIC_SetPriority(SysTick_IRQn, 0x2);    // SysTick set to lower priority than Wi-Fi SPI bus interrupt
//#define NVIC_ADC_IRQ        NVIC_SetPriority(ADC0_IRQn, 0x3);       // ADC is the lowest of all

// Wlan controls
#define WLAN_ISF_PCR        PORTA->PCR[16]
#define WLAN_ISF_ISFR       PORTA->ISFR
#define WLAN_ISF_MASK       (1<<16)

#define WLAN_ASSERT_CS      wlan_cs = 0;   //CS : active low
#define WLAN_DEASSERT_CS    wlan_cs = 1;

#define WLAN_ASSERT_EN      wlan_en = 1;   //EN : active high
#define WLAN_DEASSERT_EN    wlan_en = 0;

#define WLAN_READ_IRQ       wlan_int

#define WLAN_ENABLE_IRQ     NVIC_EnableIRQ(PORTA_IRQn);
#define WLAN_DISABLE_IRQ    NVIC_DisableIRQ(PORTA_IRQn);

#define WLAN_IRQ_PIN_CREATE         InterruptIn wlan_int (PTA16);
#define WLAN_EN_PIN_CREATE          DigitalOut  wlan_en  (PTA13);
#define WLAN_CS_PIN_CREATE          DigitalOut  wlan_cs  (PTD0);
#define WLAN_SPI_PORT_CREATE        SPI wlan(PTD2, PTD3, PTC5); // mosi, miso, sclk

#define WLAN_SPI_PORT_INIT          wlan.format(8,1);
#define WLAN_SPI_SET_FREQ           wlan.frequency(12000000);
#define WLAN_SPI_SET_IRQ_HANDLER    wlan_int.fall(&WLAN_IRQHandler);

#define WLAN_SPI_WRITE              wlan.write(*data++);
#define WLAN_SPI_READ               wlan.write(0x03);          // !! DO NOT MODIFY the 0x03 parameter (CC3000 will not respond).

API documentation

Due to a little problem with the links on the mbed site, the API documentation is not directly accessible (will be solved in a next release).
Currently, it is only accessible by adding modules.html to the API doc link: http://mbed.org/users/frankvnk/code/CC3000_Hostdriver/docs/tip/modules.html


All wikipages