Important changes to repositories hosted on mbed.com
Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.
To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.
It is also possible to export all your personal repositories from the account settings page.
Dependencies: MODSERIAL USBDevice_for_Rev_C_HW mbed
Fork of mbed_sv_firmware_with_init by
main.cpp
- Committer:
- bob_tpc
- Date:
- 2015-06-05
- Revision:
- 22:5707b236cbdb
- Parent:
- 19:d3bef4fbab69
- Child:
- 23:52504c8f63c5
File content as of revision 22:5707b236cbdb:
/**
* Copyright (c) 2015 The Positive Charge, LLC for Supervision, LLC
* @file main.cpp
* @date 2015-06-04
* @brief Freescale KL25Z firmware for USB-RFID adapter
*
* This firmware provides communication from a PC's USB host port to the following peripherals:
* RFID-FE over UART - SuperVision RFID reader module
* VL6180X over I2C - ST Microelectronics proximity and ambient light sensor
* GPIO - two LEDs and several control signals for the RFID module
* EEPROM - over I2C - Generic 24LC16B (untested since first revision prototype hardware does not have an EEPROM)
*
* Revision History
* 2014-11-01
* For Rev A Hardware - No EEPROM, single-byte GPIO
*
* 2015-03-01
* For Rev B and C Hardware - Includes EEPROM, single-byte GPIO
*
* 2015-06-04
* For Rev C Hardware - Includes EEPROM, 2-byte GPIO allows extra pins on LED connector to be used.
* - Includes EEPROM storage of USB string descriptors and RFID command for Proximity interrupt
* - Includes USB initialization update and added code to send RFID command on Proximity interrupt
*
*/
// mbed.org headers
#include "mbed.h" // main mbed.org libraries
#include "USBDevice.h"
#include "USBSerial.h" // USB CDC drivers
#include "MODSERIAL.h" // UART drivers - MODSERIAL allows block writes compared to the mbed driver
// Supervision-specific headers
#include "SV_USBConfig.h" // Default USB strings for initial power-up.
#include "ProxInit.h" // VL6180X default initial values - *not* calibrated
// Constants
#define LEDON 0 // Low active for LEDs - turns LED on
#define LEDOFF 1 // Low active for LEDs - turns LED off
#define TRUE 1 // Boolean true and false
#define FALSE 0
// Error return values
#define ERR_NONE 0x00 // Success
#define ERR_CDC_BAD_CMD 0x01 // First byte of PC to USB board needs to be 0xBB, 0xCC, 0xDD or 0xEE;
#define ERR_CDC_NO_TX_ENDMARK 0xA1 // message for no endmark on message to PC
#define ERR_UART_NOT_WRITEABLE 0xB1 // UART has no buffer space
#define ERR_UART_NOT_READABLE 0xB2 // UART has no buffer space
#define ERR_UART_NO_TX_ENDMARK 0xB3 // message for UART has no 0x7E end-mark
#define ERR_UART_NO_RX_ENDMARK 0xB4 // message received from UART has no end-mark
#define ERR_I2C_NOT_WRITEABLE 0xC1 // I2C has no buffer space
#define ERR_I2C_NO_TX_ENDMARK 0xC2 // message for I2C has no 0x7E end-mark
#define ERR_I2C_NO_RX_ENDMARK 0xC3 // message received from I2C has no end-mark
#define ERR_I2C_WRITE_TOO_LARGE 0x16 // message for I2C write is too large (16 bytes max)
#define ERR_NOT_IMPLEMENTED 0xFF // method has not yet been implemented
// I2C addresses and parameters
#define PROX (0x29 << 1) // default I2C address of VL6180X, shift into upper 7 bits
#define EEPROM (0xA0) // default I2C address of EEPROM, already shifted
#define I2CRATE 400000 // I2C speed
// UART-RFID baud rate
#define RFIDBAUD 115200 // RFID-FE board default rate = 115.2Kbps
#define BUFFERSIZE 128 // default buffer sizes
#define RFIDLENLOW 5 // RFID message length location (length is 2 bytes)
// Peripherals
USBSerial cdc; // CDC Class USB-Serial adapter. Needs custom INF, but uses existing Windows CDC drivers.
MODSERIAL uart(PTA2, PTA1); // UART port connected to RFID-FE board
I2C i2c(PTB1, PTB0); // I2C port connected to VL6180X and EEPROM - note addresses above)
// GPIO signals
DigitalOut led_err(PTC1); // Red LED shows error condition (active low)
DigitalOut led_com(PTC2); // Yellow LED shows communication activity (active low)
DigitalOut rfid_int(PTD4); // RFID FE power control (active high)
DigitalOut rfid_isp(PTD5); // RFID FE In-System Programming (active high)
DigitalOut rfid_rst(PTD6); // RFID FE Reset (active high)
DigitalOut rfid_pwr(PTE30); // RFID power switch on USB board (active high for prototype 1, low for all others)
DigitalIn rfid_hot(PTE0); // RFID over-current detection on USB board power switch (active low)
InterruptIn prox_int(PTD7); // Proximity sensor interrupt (active low)
DigitalOut ee_wp(PTC5); // EEPROM Write Protect (active high)
DigitalInOut gpio_0(PTC3); // Extra GPIO on LED connector, pin 6
DigitalInOut gpio_1(PTC4); // Extra GPIO on LED connector, pin 7
DigitalOut gpio_7(PTA4); // Extra GPIO output on LED connector, pin 3 - pin supports PWM for buzzer, not implemented here
// global buffers & variables
uint8_t led_com_state = LEDOFF; // initial LED state
uint8_t prox_irq_state = 0; // interrupt state passed from service routine
uint8_t usb_irq_state = 0; // interrupt state passed from service routine
uint8_t gpio_values = 0x00; // register to read GPIO values
uint8_t cdc_buffer_rx[BUFFERSIZE]; // buffers for cdc (USB-Serial port on PC)
uint8_t cdc_buffer_tx[BUFFERSIZE];
uint8_t uart_buffer_rx[BUFFERSIZE]; // buffers for uart (RFID-FE board)
uint8_t uart_buffer_tx[BUFFERSIZE];
uint8_t gpio_buffer[BUFFERSIZE]; // buffer for GPIO messages
char i2c_buffer[BUFFERSIZE]; // buffer for I2C devices - Proximity sensor and EEPROM - up to BUFFERSIZE bytes data payload for EEPROM, up to 4 for proximity
char prox_irq_msg[BUFFERSIZE]; // buffer for automatic RFID message on proximity interrupt
int i, j; // general index variables
int status = 0x00; // return value
// USB config descriptor strings
// These are held in SV_USBConfig.h, and only used during initial bring-up after manufacturing
char mfg_str[0x2E] = {SV_MFG}; // Default USB strings - Manufacturer
char mfg_str_cnt = SV_MFG_CNT;
char ser_str[0x2E] = {SV_SER}; // Default USB strings - Serial Number
char ser_str_cnt = SV_SER_CNT;
char des_str[0x3E] = {SV_DES}; // Default USB strings - Product Description
char des_str_cnt = SV_DES_CNT;
// These next functions are modified from the original USBDevice.cpp and USBCDC.cpp mbed drivers
// in order to allow custom USB descriptor strings.
/**
* @name USBDevice::stringImanufacturerDesc
* @name USBDevice::stringIserialDesc
* @name USBDevice::stringIproductDesc
* @name USBCDC::stringIproductDesc
* @brief Sets custom USB Config Descriptor Strings
*
* These methods are modified from the original to allow custom USB config descriptor strings.
* The original (in USBDevice.cpp and USBCDC.cpp) are hard-coded for generic mbed.org values
* The values used in these methods are read from the EEPROM. Especially important is allowing
* a custom USB Serial Number, which will be written to the EEPROM during the factory test.
*
* @param [in] none
* @retval stringImanufacturerDescriptor
* @retval stringIserialDescriptor
* @retval stringIproductDescriptor
* @retval stringIproductDescriptor
*/
// MODIFIED to allow custom strings
uint8_t * USBDevice::stringImanufacturerDesc() {
static uint8_t stringImanufacturerDescriptor[0x30];
stringImanufacturerDescriptor[0] = mfg_str_cnt;
stringImanufacturerDescriptor[1] = STRING_DESCRIPTOR;
for (int i = 0; i < sizeof(mfg_str); i++){
stringImanufacturerDescriptor[i+2] = mfg_str[i];
}
return stringImanufacturerDescriptor;
}
// MODIFIED to allow custom strings
uint8_t * USBDevice::stringIserialDesc() {
static uint8_t stringIserialDescriptor[0x30];
stringIserialDescriptor[0] = ser_str_cnt;
stringIserialDescriptor[1] = STRING_DESCRIPTOR;
for (int i = 0; i < sizeof(ser_str); i++){
stringIserialDescriptor[i+2] = ser_str[i];
}
return stringIserialDescriptor;
}
// MODIFIED to allow custom strings
uint8_t * USBDevice::stringIproductDesc() {
static uint8_t stringIproductDescriptor[0x40];
stringIproductDescriptor[0] = des_str_cnt;
stringIproductDescriptor[1] = STRING_DESCRIPTOR;
for (int i = 0; i < sizeof(des_str); i++){
stringIproductDescriptor[i+2] = des_str[i];
}
return stringIproductDescriptor;
}
// MODIFIED to allow custom strings
uint8_t * USBCDC::stringIproductDesc() {
static uint8_t stringIproductDescriptor[0x40];
stringIproductDescriptor[0] = des_str_cnt;
stringIproductDescriptor[1] = STRING_DESCRIPTOR;
for (int i = 0; i < sizeof(des_str); i++){
stringIproductDescriptor[i+2] = des_str[i];
}
return stringIproductDescriptor;
}
/**
* @name prox_irq
* @brief Sets interrupt variable for use in the main loop.
* The interrupt is triggered by the VL6180X GPIO1 (IRQ output)
*
* @param [in] none
* @param [out] prox_irq_state = 1 indicates an interrupt occured.
*/
void prox_irq(void)
{
prox_irq_state = 1;
led_com.write(LEDON); // Turn on COM LED until interrupt is serviced
}
/**
* @name usb_irq
* @brief Sets interrupt variable for use in the main loop.
* The interrupt is triggered when the host PC has sent data to the CDC port.
*
* @param [in] none
* @param [out] usb_irq_state = 1 indicates an interrupt occured.
*/
void usb_irq(void)
{
usb_irq_state = 1;
}
/**
* @name init_periph
* @brief Initializes the KL25Z peripheal interfaces
* KL25Z interfaces:
* USB - Initializes USB config descriptors
* UART - Connects to SuperVision RFID-FE module
* I2C - Configures to the ST VL6180X proximity/ambient light sensor device
* I2C - Reads configuration data from EEPROM
* GPIO - Includes two LEDs and signals to control RFID reader.
*
* @param [in] none
* @param [out] error status (0 = no error)
*
* @retval error state
*/
int init_periph(void)
{
int i2c_err; // return value
char temploc = 0x00; // temporary values
char temp[] = {0,0};
char i2c_page = 0;
char prox_ee[254] = {0}; // buffer for Proximity initialization values stored
// in EEPROM, especially the cover glass calibration
// Set up peripherals on KL25Z
led_err.write(LEDOFF); // Start with leds
led_com.write(LEDOFF);
// Check EEPROM for programmed USB string descriptors. These are held in BANK ZERO (I2C address = EEPROM | 0 << 1)
// Factory test should initialize the EEPROM
//
// First two bytes of bank zero will be "SV" if programmed.
// Bank 0x10 holds Manufacturer string
// Bank 0x40 holds Serial Number string
// Bank 0x70 holds Product Description string
i2c_page = EEPROM | 0 << 1; // set EEPROM page = bank 0
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte (just index), no stop at end.
i2c.read(i2c_page, temp, 2, 0); // i2c address+bank 0, variable location, 2 bytes (just data), stop at end.
if ((temp[0] == 'S') && (temp[1] == 'V')) {
led_com.write(LEDON);
// Read Manufacturer String
temploc = 0x10;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, count index, 1 byte, no stop at end
i2c.read(i2c_page, &mfg_str_cnt, 1, 0); // i2c address+bank 0, mfg string size, 1 byte, stop at end
temploc = 0x11;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte, no stop at end
i2c.read(i2c_page, mfg_str, mfg_str_cnt, 0); // i2c address+bank 0, mfg string, string size, stop at end
// Read Serial Number string
temploc = 0x40;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte no stop at end
i2c.read(i2c_page, &ser_str_cnt, 1, 0); // i2c address+bank 0, serial number string size, 1 byte, stop at end
temploc = 0x41;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte, no stop at end
i2c.read(i2c_page, ser_str, ser_str_cnt, 0); // i2c address+bank 0, serial number string, string size, stop at end
// Read Product Description String
temploc = 0x70;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte, no stop at end
i2c.read(i2c_page, &des_str_cnt, 1, 0); // i2c address+bank 0, description string size, 1 byte, stop at end
temploc = 0x71;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 0, memory index, 1 byte, no stop at end
i2c.read(i2c_page, des_str, des_str_cnt, 0); // i2c address+bank 0, description string, string size, stop at end
led_com.write(LEDOFF);
}
// Prox & EEPROM
ee_wp.write(0); // no write protection on EEPROM
i2c.frequency(I2CRATE); // I2C speed = 400Kbps
// Get the VL6180X register values from the ProxInit.h header and program them to the Proximity Sensor (from VL6180X app notes)
for (i = 0; i < sizeof(proxinit); i += 3){ // Initialize VL6180X with default values, calibration data sent later
i2c_err = i2c.write(PROX, &proxinit[i], 3, 0); // I2C Address, pointer to buffer, number of bytes (for index + data), stop at end.
// also includes taking off the "Fresh out of Reset" flag.
if (i2c_err){
led_err.write(LEDON); // Turn on both LEDs
led_com.write(LEDON); // We can't write to the proximity sensor
return i2c_err;
}
}
// Get Supervision-specific register values and program them to the Proximity Sensor (calibration, other operating features)
i2c_page = EEPROM | 1 << 1; // set EEPROM page = bank 1
temploc = 0;
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 1, memory index, 1 byte (just index), no stop at end.
i2c.read(i2c_page, temp, 2, 0); // i2c address+bank 1, variable location, 2 bytes (just data), stop at end.
if ((temp[0] == 'S') && (temp[1] == 'V')) {
led_com.write(LEDON);
// Read values
temploc = 0x02; // Values start here. Since this section is mostly one-byte values with two-byte
// addresses, 2- and 4-byte registers are individually addressed
i2c.write(i2c_page, &temploc, 1, 1); // i2c address+bank 1, location 2, 1 byte, no stop at end - read the whole bank
i2c.read(i2c_page, prox_ee, sizeof(prox_ee), 0); // i2c address+bank 1, buffer location, 1 byte, stop at end
for (i = 0; i < sizeof(prox_ee); i += 3){ // Initialize VL6180X with default values, calibration data sent later
if ((prox_ee[i] == 0xFF) && (prox_ee[i+1] == 0xFF)){
break; // No more values are in the EEPROM (blank / erased = 0xFF)
}
else {
i2c_err = i2c.write(PROX, &prox_ee[i], 3, 0); // I2C Address, pointer to buffer, number of bytes (for index + data), stop at end.
// also includes taking off the "Fresh out of Reset" flag.
if (i2c_err){
led_err.write(LEDON); // Turn on both LEDs
led_com.write(LEDON); // We can't write to the proximity sensor
return i2c_err;
}
}
}
led_com.write(LEDOFF);
}
// Enable the Proximity interrupt
prox_int.mode(PullUp); // pull up proximity sensor interrupt at MCU
prox_int.fall(&prox_irq); // VL6180X interrupt is low active
prox_int.enable_irq(); // Enable proximity interrupt inputs
// "Fresh-out-of-reset" register was automatically set to 0x01 after boot
prox_ee[0] = 0x00;
prox_ee[1] = 0x16;
prox_ee[2] = 0x00;
i2c.write(PROX, prox_ee, 3, 0); // Remove "Fresh out of Reset" flag to allow normal operation
cdc.attach(&usb_irq); // Attach USB interrupt
usb_irq_state = 0; // Ensure interrupt flag is not set after setup
// RFID
uart.baud(RFIDBAUD); // RFID-FE baud rate
rfid_int = 0; // RFID FE power control (active high)
rfid_isp = 0; // RFID FE In-System Programming (active high)
rfid_rst = 1; // RFID FE Reset (active high)
rfid_pwr = 0; // RFID power switch on USB board (active low for all others)
wait(0.25); // wait 250ms before...
rfid_rst = 0; // ... taking RFID out of reset
wait(0.25);
while(!uart.readable()) { // wait for RESET message from RFID
led_err.write(LEDON); // flash LED until it arrives
wait(0.1); // This is a good way to see if the RFID cable is properly seated
led_err.write(LEDOFF);
wait(0.1);
}
uart.txBufferFlush(); // clear out UART buffers - we don't need the reset message
uart.rxBufferFlush();
// LEDs // Cycle through the LEDs.
led_err.write(LEDON);
led_com.write(LEDON);
wait(0.5);
led_err.write(LEDOFF);
wait(0.5);
led_com.write(LEDOFF);
return ERR_NONE;
}
/**
* @name rfid_wr
* @brief Forwards command to RFID reader
*
* RFID reader is connected to the KL25Z UART interface. The host PC will have a USB CDC class COM port device driver.
* The host PC sends the RFID command over the COM port. Messages destined for the RFID reader (0xBB leading byte) are
* forwarded as-is to the RFID reader. The reader then responds in kind. All RFID commands are described in the
* RFID-FE module manual.
*
* @param [out] uart_buffer_tx - messages to the RFID reader
*
* @retval ERR_NONE No error
* @retval ERR_UART_NOT_WRITEABLE UART has no buffer space
* @retval ERR_UART_NO_TX_ENDMARK message for UART has no 0x7E end-mark
* @example
* BB 00 03 00 01 02 7E 2E C9 = read
*/
int rfid_wr(void)
{
int em_pos = 0;
for (i = 0; i < sizeof(uart_buffer_tx); i++) {
if (uart_buffer_tx[i] == 0x7E) em_pos = (i + 1); // allows 0x7E to appear in the data payload - uses last one for end-mark
}
if (em_pos == 0) {
led_err.write(LEDON); // end mark never reached
return ERR_UART_NO_TX_ENDMARK;
}
if (!uart.writeable()) {
led_err.write(LEDON);
return ERR_UART_NOT_WRITEABLE; // if no space in uart, return error
}
for (i = 0; i < (em_pos + 2); i++) {
uart.putc(uart_buffer_tx[i]); // send uart message
}
return ERR_NONE;
}
/**
* @name prox_msg_wr
* @brief Forwards command to VL6180X sensor
*
* Proximity/ALS reader is connected to the KL25Z I2C interface.
* The host PC sends the sensor command over the COM port. Messages destined for the proximity/ALS sensor (0xCC leading byte) are
* forwarded to the proximity/ALS sensor after removing the leading byte and trailing bytes (0x7E endmark plus 2 bytes).
* The sensor then responds in kind. Firmware re-attaches the leading 0xCC and trailing bytes before sending the response over the
* CDC port to the host PC.
*
* I2C-prox messages:
* - 0xCC (byte) leading value = 0xCC
* - r/w# (byte) 0 = write, 1 = read
* - number of data bytes(byte) 0 to 32 (size of declared buffers)
* - index (2 bytes) 12-bit VL6801X register offset, high byte first
* - data (n bytes) number of data bytes noted above
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* Multiple registers can be read or written with single prox_msg_rd() or prox_msg_wr(). Location address increments for each byte.
* VL6180X registers are defined in the sensor datasheet.
*
* @param [in] i2c_buffer - messages to and from the VL6180X and EEPROM
*
* @retval 0 No error
* @retval 1 I2C bus has NAK'd / failure
*
* @param [in/out] i2c_buffer - messages to and from the i2c bus - see above
*
*/
int prox_msg_wr() // write proximity I2C register
{
int i2c_err;
i2c_err = i2c.write(PROX, &i2c_buffer[3], i2c_buffer[2] + 2, 0);// I2C Address, pointer to buffer, number of bytes (for index + data), stop at end.
return i2c_err; // 0 = ACK received, 1 = NAK/failure
}
/**
* @name prox_msg_rd
* @brief retrieves response from VL6180X sensor
*
* Proximity/ALS reader is connected to the KL25Z I2C interface.
* The host PC sends the sensor command over the COM port. Messages destined for the proximity/ALS sensor (0xCC leading byte) are
* forwarded to the proximity/ALS sensor after removing the leading byte and trailing bytes (0x7E endmark plus 2 bytes).
* The sensor then responds in kind. Firmware re-attaches the leading 0xCC and trailing bytes before sending the response over the
* CDC port to the host PC.
*
* I2C-prox messages:
* - 0xCC (byte) leading value = 0xCC
* - r/w# (byte) 0 = write, 1 = read
* - number of data bytes(byte) 0 to 32 (size of declared buffers)
* - index (2 bytes) 12-bit VL6801X register offset, high byte first
* - data (n bytes) number of data bytes noted above
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* Multiple registers can be read or written with single prox_msg_rd() or prox_msg_wr(). Location address increments for each byte.
* VL6180X registers are defined in the sensor datasheet.
*
* @param [in/out] i2c_buffer - messages to and from the i2c bus - see above
*
* @retval 0 No error
* @retval 1 I2C bus has NAK'd / failure
*
*
*/
int prox_msg_rd()
{
int i2c_err;
i2c_err = i2c.write(PROX, &i2c_buffer[3], 2, 1); // I2C Address, pointer to buffer (just the index), index, number of bytes (2 for index), no stop at end.
i2c_err |= i2c.read(PROX, &i2c_buffer[5], i2c_buffer[2], 0); // I2C Address, pointer to buffer (just the data), number of data bytes, stop at end.
return i2c_err; // 0 = ACK received, 1 = NAK/failure
}
/**
* @name gpio_rd
* @brief retrieves instantaneous value of GPIO pins
*
* GPIO signals are defined directly off of the KL25Z.
* The host PC sends the GPIO command over the COM port. With a 0xDD leading byte in the message, the state of the GPIO signals are read and returned.
* This allows a read-modify-write GPIO sequence.
*
* GPIO messages:
* - 0xDD (byte) leading value = 0xDD
* - r/w# (byte) 0 = write, 1 = read
* - data (2 bytes) see below
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* GPIO data bits - First Byte
* - 0 LED - Error 0 = on, 1 = off
* - 1 LED - Comm state 0 = on, 1 = off
* - 2 RFID interrupt input 0 = off, 1 = on (inverted in h/w)
* - 3 RFID in-system-prog 0 = off, 1 = on (inverted in h/w)
* - 4 RFID reset 0 = off, 1 = on (inverted in h/w)
* - 5 RFID power enable for first prototype, 0 = off, 1 = on / for production, 0 = on, 1 = off
* - 6 RFID over-current 0 = overcurrent detected, 1 = OK
* - 7 Proximity interrupt 0 = interrupt, 1 = idle (This pin may not return anything meaningful here. The interrupt is edge triggered).
*
* GPIO data bits - Second Byte
* - 0 GPIO on pin 6 of LED connector - I/O
* - 1 GPIO on pin 7 of LED connector - I/O
* - 2-6 - unused bits, output don't care, input read as zero
* - 7 GPIO on pin 3 of LED connector - OUTPUT only, inverted logic, open drain with 1K pull-up, read as zero
*
* @param [in/out] gpio_buffer - GPIO states
*
* @retval 0 No error
*
*/
int gpio_rd()
{
gpio_buffer[2] = ( led_err.read() & 0x01); // read first byte of the GPIO pins
gpio_buffer[2] |= ((led_com_state << 1) & 0x02); // use of led_com_state allows the LED to remain ON in the main loop if desired
gpio_buffer[2] |= ((rfid_int.read() << 2) & 0x04);
gpio_buffer[2] |= ((rfid_isp.read() << 3) & 0x08);
gpio_buffer[2] |= ((rfid_rst.read() << 4) & 0x10);
gpio_buffer[2] |= ((rfid_pwr.read() << 5) & 0x20);
gpio_buffer[2] |= ((rfid_hot.read() << 6) & 0x40);
gpio_buffer[2] |= ((prox_int.read() << 7) & 0x80);
gpio_buffer[3] = ( gpio_0.read() & 0x01); // read second byte of the GPIO pins
gpio_buffer[3] |= (( gpio_1.read() << 1) & 0x02);
gpio_buffer[3] |= (( 0 << 2) & 0x04); // bits 2-7 always return zero
gpio_buffer[3] |= (( 0 << 3) & 0x08);
gpio_buffer[3] |= (( 0 << 4) & 0x10);
gpio_buffer[3] |= (( 0 << 5) & 0x20);
gpio_buffer[3] |= (( 0 << 6) & 0x40);
gpio_buffer[3] |= (( 0 << 7) & 0x80);
return ERR_NONE;
}
/**
* @name gpio_wr
* @brief sets value of GPIO pins
*
* GPIO signals are defined directly off of the KL25Z.
* The host PC sends the GPIO command over the COM port. With a 0xDD leading byte in the message, the state of the GPIO signals are read and returned.
* This allows a read-modify-write GPIO sequence.
*
* GPIO messages:
* - 0xDD (byte) leading value = 0xDD
* - r/w# (byte) 0 = write, 1 = read
* - data (2 bytes) see below
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* GPIO data bits - First Byte:
* - 0 LED - Error 0 = on, 1 = off
* - 1 LED - Comm state 0 = on, 1 = off
* - 2 RFID interrupt input 0 = off, 1 = on (inverted in h/w)
* - 3 RFID in-system-prog 0 = off, 1 = on (inverted in h/w)
* - 4 RFID reset 0 = off, 1 = on (inverted in h/w)
* - 5 RFID power enable for first prototype, 0 = off, 1 = on / for production, 0 = on, 1 = off
* - 6 RFID over-current 0 = overcurrent detected, 1 = OK
* - 7 Proximity interrupt 0 = interrupt, 1 = idle (This pin may not return anything meaningful here. The interrupt is edge triggered).
*
* GPIO data bits - Second Byte
* - 0 GPIO on pin 6 of LED connector - I/O
* - 1 GPIO on pin 7 of LED connector - I/O
* - 2-6 - unused bits, output don't care, input read as zero
* - 7 GPIO on pin 3 of LED connector - OUTPUT only, inverted logic, open drain with 1K pull-up, read as zero
*
* @param [in/out] gpio_buffer - GPIO states
*
* @retval 0 No error
*
*/
int gpio_wr()
{
if ((gpio_buffer[2] & 0x02) == 0x00) { // Set the desired state of the yellow LED
led_com_state = LEDON;
} else {
led_com_state = LEDOFF;
}
led_err.write(gpio_buffer[2] & 0x01); // Write GPIO bits - first byte
led_com.write(led_com_state); // use of led_com_state allows the LED to remain ON in the main loop if desired
rfid_int.write(gpio_buffer[2] & 0x04);
rfid_isp.write(gpio_buffer[2] & 0x08);
rfid_rst.write(gpio_buffer[2] & 0x10);
rfid_pwr.write(gpio_buffer[2] & 0x20);
gpio_0.write(gpio_buffer[3] & 0x01); // Write GPIO bits - second byte
gpio_1.write(gpio_buffer[3] & 0x02); // Write GPIO bits - second byte
gpio_7.write(gpio_buffer[3] & 0x80); // Write GPIO bits - second byte
return ERR_NONE;
}
/**
* @name eeprom_msg_wr
* @brief writes data to the I2C EEPROM
*
* The EEPROM is connected to the KL25Z I2C interface.
* The host PC sends the sensor command over the COM port. Messages destined for the EERPOM (0xEE leading byte) are
* forwarded to the EEPROM after removing the leading byte and trailing bytes (0x7E endmark plus 2 bytes).
* Firmware re-attaches the leading 0xEE and trailing bytes before sending the response over the
* CDC port to the host PC.
*
* I2C-EEPROM messages:
* - 0xEE (byte) leading value = 0xEE
* - r/w# (byte) 0 = write, 1 = read
* - number of data bytes(byte) 0 to 16 bytes for write
* - block (byte) lower 3 bits are logically OR'd with the I2C address
* - address (byte) memory location within block
* - data (n bytes) number of data bytes noted above
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* Multiple memory locations can be read or written with single eeprom_msg_rd() or eeprom_msg_wr(). Location address increments for each byte.
* Read/Write sequences are defined in the 24LC16B datasheet.
*
* This practically the the same as the proximity calls, except the index/location is only one byte and the block select is part of the I2C address byte.
*
* @param [in] i2c_buffer - messages to and from the VL6180X and EEPROM
*
* @retval 0 No error
* @retval 1 I2C bus has NAK'd / failure
* @retval ERR_I2C_WRITE_TOO_LARGE buffer size too large
*
* @param [in/out] i2c_buffer - messages to and from the i2c bus - see above
*
*/
int eeprom_msg_wr() // write proximity I2C register
{
int i2c_err = ERR_NONE;
char wr[2] = {0xFF, 0xFF};
for (i = 0; i < i2c_buffer[2]; i++){ // done with single-byte writes to avoid addressing wrap-around
wr[0] = i2c_buffer[4]+i;
wr[1] = i2c_buffer[5+i];
i2c_err |= i2c.write((EEPROM | (i2c_buffer[3] << 1 )), wr, 2, 0);
while ( i2c.write(EEPROM | (i2c_buffer[3] << 1 ))); // wait until write is done (EEPROM will ACK = 0 for single byte i2c.write)
// I2C Address & block select, pointer to buffer, 2 bytes (address + one data), stop at end.
}
return i2c_err; // 0 = ACK received, 1 = NAK/failure
}
/**
* @name eeprom_msg_rd
* @brief read data from the I2C EEPROM
* @note EEPROM only availalbe on REV B and later
*
* The EEPROM is connected to the KL25Z I2C interface.
* The host PC sends the sensor command over the COM port. Messages destined for the EERPOM (0xEE leading byte) are
* forwarded to the EEPROM after removing the leading byte and trailing bytes (0x7E endmark plus 2 bytes).
* Firmware re-attaches the leading 0xEE and trailing bytes before sending the response over the
* CDC port to the host PC.
*
* I2C-EEPROM messages:
* - 0xEE (byte) leading value = 0xEE
* - r/w# (byte) 0 = write, 1 = read
* - number of data bytes(byte) 0 to 128 bytes for read (size of declared buffer)
* - block (byte) lower 3 bits are logically OR'd with the I2C address
* - address (byte) memory location within block
* - data (n bytes) number of data bytes noted above
* - end_mark (byte) 0x7E
* - dummy (2 bytes) values are don't-care - fillers for RFID CRC bytes
*
* Multiple memory locations can be read or written with single eeprom_msg_rd() or eeprom_msg_wr(). Location address increments for each byte.
* Read/Write sequences are defined in the 24LC16B datasheet.
*
* This practically the the same as the proximity calls, except the index/location is only one byte and the block select is part of the I2C address byte.
*
* @param [in/out] i2c_buffer - messages to and from the VL6180X and EEPROM
*
* @retval [none]0 No error
* @retval 1 I2C bus has NAK'd / failure
*
* @param [in/out] i2c_buffer - messages to and from the i2c bus - see above
*
*/
int eeprom_msg_rd()
{
int i2c_err;
i2c_err = i2c.write((EEPROM | (i2c_buffer[3] << 1)), &i2c_buffer[4], 1, 1);
// I2C Address & block select, pointer to buffer (just the index), index, number of bytes (for address + data), no stop at end.
i2c_err |= i2c.read((EEPROM | (i2c_buffer[3] << 1)), &i2c_buffer[5], i2c_buffer[2], 0);
// I2C Address & block select, pointer to buffer (just the data), number of data bytes, stop at end.
return i2c_err; // 0 = ACK received, 1 = NAK/failure
}
/**
* @name main
* @brief Main firmware loop
*
* @returns [none]
*/
int main(void)
{
int em_pos = 0; // end of message count - allows multiple 0x7e in message.
char msgcount;
char temploc;
char autorange[] = {0x00, 0x18, 0x00}; // Proximity sensor automatic measurement. Set last byte = 0x03 to start
char proxintclr[] = {0x00, 0x15, 0x07}; // Clear proximity interrupt
char i2c_addr = (EEPROM | (2 << 1)); // EEPROM base address is 0xA0 (already shifted). Bank 2 in use here, shifted for I2C addressing.
init_periph(); // initialize everything
while(1) { // main loop
led_com.write(led_com_state); // turn off communication LED unless it was specifically turned on by GPIO command
if (prox_irq_state == 1) { // process the proximity interrupt
if (prox_irq_msg[0] != 0xBB){ // no message to send to RFID
cdc_buffer_tx[0] = 0xFF; // just send a dummy message back to the host
cdc_buffer_tx[1] = 0x7E;
cdc_buffer_tx[2] = 0x0F;
cdc_buffer_tx[3] = 0xF0;
cdc.writeBlock(cdc_buffer_tx, 4);
led_err.write(LEDON); // we shouldn't get here
}
else{
msgcount = prox_irq_msg[2] + 6; // See RFID-FE manual for message construction
for (i = 0; i < msgcount; i++) {
uart.putc(prox_irq_msg[i]); // send message to RFID-FE module for a single read
}
}
prox_irq_state = 0; // reset proximity interrupt state
wait(0.5); // wait 1/2 sec so the COM LED can be seen
led_com.write(led_com_state); // turn off COM LED if not on by GPIO (it was turned on in the ISR)
i2c.write(PROX, proxintclr, 3, 0); // i2c prox sensor, interrupt clear message, 3 bytes, stop at end
}
if (uart.readable()) { // message availalbe from rfid (all responses (0x01) and broadcast (0x02))
int rfid_len = 0;
led_com.write(LEDON);
for (i = 0; i < (RFIDLENLOW); i++) { // Get first part of message to find out total count
uart_buffer_rx[i] = uart.getc(); // get a byte from rfid
}
rfid_len = ((uart_buffer_rx[i-2]<<8) + (uart_buffer_rx[i-1])); // location of message length for RFID
for (i = RFIDLENLOW; i < (RFIDLENLOW + rfid_len + 3); i++) { // get the reset of the message
uart_buffer_rx[i] = uart.getc(); // get a byte from rfid
}
for (i = 0; i < (RFIDLENLOW + rfid_len + 3); i++) { // copy the message to the USB buffer
cdc_buffer_tx[i] = uart_buffer_rx[i];
}
cdc.writeBlock(cdc_buffer_tx, (RFIDLENLOW + rfid_len + 3)); // send the RFID message to the PC
led_com.write(led_com_state);
}
if (usb_irq_state == 1) { // message available from PC
usb_irq_state = 0; // allow another USB interrupt
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
if (cdc.readable()) cdc_buffer_rx[i] = cdc._getc(); // read data from USB side
}
if ((cdc_buffer_rx[0] == 'A') && (cdc_buffer_rx[1] == 'T')) { // check for Hayes command and ignore it
break; // Linux systems will enumerate as ttyACMx
} // and attempt to initialize the non-existent modem
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
if (cdc_buffer_rx[i] == 0x7E) { // check for rfid end mark in outbound message
em_pos = (i + 1);
}
}
led_com.write(LEDON); // Message received - turn on LED
if (em_pos == 0) { // end mark never reached
led_err.write(LEDON);
break;
}
switch(cdc_buffer_rx[0]) { // check first byte for "destination"
case 0xBB: // RFID-FE
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
uart_buffer_tx[i] = cdc_buffer_rx[i]; // copy USB message to UART for RFID
}
status = rfid_wr(); // send buffer to RFID and get response according to RFID board
break;
case 0xCC: // Proximity Sensor
led_com.write(LEDON);
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
i2c_buffer[i] = cdc_buffer_rx[i]; // copy USB message to buffer for I2C
}
if (i2c_buffer[1] == 1) // I2C read = 1
status = prox_msg_rd(); // read the requested data
else if (i2c_buffer[1] == 0) // I2C write = 0
status = prox_msg_wr(); // send buffer to proximity sensor and get response
if (status) led_err.write(LEDON); // we shouldn't get here
em_pos = 0;
for (i = 0; i < sizeof(cdc_buffer_tx); i++) {
cdc_buffer_tx[i] = i2c_buffer[i]; // copy RFID response back to USB buffer
if (cdc_buffer_tx[i] == 0x7E) {
em_pos = (i + 1); // allows 0x7E to appear in the data payload - uses last one for end-mark
}
}
if (em_pos == 0) {
led_err.write(LEDON); // end mark never reached
break;
}
cdc.writeBlock(cdc_buffer_tx, (em_pos + 2));
led_com.write(led_com_state);
break;
case 0xDD: // GPIO (LEDs and RFID-FE control)
led_com.write(LEDON);
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
gpio_buffer[i] = cdc_buffer_rx[i]; // copy USB message to buffer for GPIO
}
if (gpio_buffer[1] == 1) // GPIO read = 1
status = gpio_rd(); // read the requested data
else if (gpio_buffer[1] == 0) // GPIO write = 0
status = gpio_wr(); // send GPIO pin data
em_pos = 0;
for (i = 0; i < sizeof(cdc_buffer_tx); i++) {
cdc_buffer_tx[i] = gpio_buffer[i]; // copy RFID response back to USB buffer
if (cdc_buffer_tx[i] == 0x7E) {
em_pos = (i + 1); // allows 0x7E to appear in the data payload - uses last one for end-mark
}
}
if (em_pos == 0) {
led_err.write(LEDON); // end mark never reached
break;
}
cdc.writeBlock(cdc_buffer_tx, (em_pos + 2));
led_com.write(led_com_state);
break;
case 0xEE: // Read/write EEPROM
led_com.write(LEDON);
for (i = 0; i < sizeof(cdc_buffer_rx); i++) {
i2c_buffer[i] = cdc_buffer_rx[i]; // copy USB message to buffer for I2C
}
if (i2c_buffer[1] == 1) // I2C read = 1
status = eeprom_msg_rd(); // read the requested data
else if (i2c_buffer[1] == 0) // I2C write = 0
status = eeprom_msg_wr(); // send buffer to EEPROM and get response
if (status) led_err.write(LEDON);
em_pos = 0;
for (i = 0; i < sizeof(cdc_buffer_tx); i++) {
cdc_buffer_tx[i] = i2c_buffer[i]; // copy RFID response back to USB buffer
if (cdc_buffer_tx[i] == 0x7E) {
em_pos = (i + 1); // allows 0x7E to appear in the data payload - uses last one for end-mark
}
}
if (em_pos == 0) {
led_err.write(LEDON); // end mark never reached
break;
}
cdc.writeBlock(cdc_buffer_tx, (em_pos + 2));
led_com.write(led_com_state);
break;
case 0xFF:
if (cdc_buffer_rx[1] > 0){
// read message sent to RFID on interrupt
temploc = 0x12;
i2c.write(i2c_addr, &temploc, 1, 1); // i2c address+bank 0, RFID message size location, 1 byte, no stop at end
i2c.read(i2c_addr, &msgcount, 1, 0); // i2c address+bank 0, RFID message size, 1 byte, stop at end
msgcount += 6; // get the real size
temploc = 0x10;
i2c.write(i2c_addr, &temploc, 1, 1); // i2c address+bank 0, RFID message location, 1 byte, no stop at end
i2c.read(i2c_addr, prox_irq_msg, msgcount, 0); // i2c address+bank 0, description string, string size, stop at end
autorange[2] = 0x03;
i2c.write(PROX, autorange, 3, 0); // Start contonuous proximity range read
}
else {
prox_irq_msg[0] = 0xFF; // clear first byte
autorange[2] = 0x00;
i2c.write(PROX, autorange, 3, 0); // Stop range read
}
break;
default:
led_err.write(LEDON); // we should never get here
while(1); // halt!
}
}
led_com.write(led_com_state);
}
}
//EOF main.cpp
