ft232r.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 /* According to POSIX.1-2001 */
   4 #include <sys/select.h>
   5 #include <string.h>
   6 #include <sys/time.h>
   7 #include <sys/types.h>
   8 #include <unistd.h>
   9 #include <termios.h>
  10 #include <fcntl.h>
  11 #include <signal.h>
  12 #include <libusb.h>
  13 #include <getopt.h>
  14
  15
  16 #define _GNU_SOURCE
  17 #include <getopt.h>
  18
  19
  20 #define I_VENDOR_NUM        0x0403
  21 #define I_PRODUCT_NUM       0x6001
  22 #define BITMODE_CBUS        0x20
  23 #define BITMODE_RESET       0x00
  24
  25 #define FTDI_SIO_SET_BITMODE 11 /* Set the bitmode */
  26 #define FTDI_SIO_READ_PINS 12   /* Read pins in bitmode */
  27
  28 #define FTDI_SIO_SET_BITMODE_REQUEST FTDI_SIO_SET_BITMODE
  29 #define FTDI_SIO_SET_BITMODE_REQUEST_TYPE 0x40
  30
  31 #define FTDI_SIO_READ_PINS_REQUEST FTDI_SIO_READ_PINS
  32 #define FTDI_SIO_READ_PINS_REQUEST_TYPE 0xC0
  33
  34 int get_device_vid()
  35 {
  36         return I_VENDOR_NUM;
  37 }
  38
  39 int get_device_pid()
  40 {
  41         return I_PRODUCT_NUM;
  42 }
  43
  44 /* Get current GPIO register from PL2303 */
  45 unsigned char gpio_read_reg(libusb_device_handle *h)
  46 {
  47         unsigned char buf;
  48         int bytes = libusb_control_transfer(
  49                 h,             // handle obtained with usb_open()
  50                 FTDI_SIO_READ_PINS_REQUEST_TYPE, // bRequestType
  51                 FTDI_SIO_READ_PINS_REQUEST,      // bRequest
  52                 0,              // wValue
  53                 0,              // wIndex
  54                 &buf,             // pointer to destination buffer
  55                 1,  // wLength
  56                 1000
  57                 );
  58         handle_error(bytes);
  59         return buf;
  60 }
  61
  62 void gpio_write_reg(libusb_device_handle *h, unsigned short reg)
  63 {
  64         int bytes = libusb_control_transfer(
  65                 h,             // handle obtained with usb_open()
  66                 FTDI_SIO_SET_BITMODE_REQUEST_TYPE, //bRequestType
  67                 FTDI_SIO_SET_BITMODE_REQUEST, // bRequest
  68                 reg,              // wValue
  69                 0,              // wIndex
  70                 0,             // pointer to destination buffer
  71                 0,  // wLength
  72                 1000
  73                 );
  74         handle_error(bytes);
  75
  76 }
  77
  78 void gpio_out(libusb_device_handle *h, int gpio, int value)
  79 {
  80         unsigned char cbus_mask;
  81
  82         if ((gpio < 0) || (gpio > 3))
  83                 return;
  84
  85         cbus_mask = gpio_read_reg(h);
  86         cbus_mask |= ((1 << gpio) << 4);
  87         if (value)
  88                 cbus_mask |= (1 << gpio);
  89         else
  90                 cbus_mask &= ~(1 << gpio);
  91         gpio_write_reg(h, (BITMODE_CBUS << 8) | cbus_mask);
  92 }
  93
  94 void gpio_in(libusb_device_handle *h, int gpio, int pullup)
  95 {
  96         unsigned char cbus_mask;
  97
  98         if ((gpio < 0) || (gpio > 3))
  99                 return;
 100
 101         cbus_mask = gpio_read_reg(h);
 102         cbus_mask &= ~((1 << gpio) << 4);
 103         gpio_write_reg(h, (BITMODE_CBUS << 8) | cbus_mask);
 104 }
 105
 106 int gpio_read(libusb_device_handle *h, int gpio)
 107 {
 108         unsigned char r = gpio_read_reg(h);
 109
 110         if ((gpio < 0) || (gpio > 3))
 111                 return 0;
 112         return (r & (1 << gpio)) ? 1 : 0;
 113 }
 114