git.zerfleddert.de Git - rigol/blob - usbtmc.c

   1 #include <string.h>
   2 #include <stdio.h>
   3 #include <stdint.h>
   4 #include <usb.h>
   5 #include <arpa/inet.h>
   6
   7 #include "usbtmc.h"
   8
   9 #define USB_TIMEOUT 50000
  10
  11 #if BYTE_ORDER == LITTLE_ENDIAN
  12 #define LE32(x) x
  13 #elif BYTE_ORDER == BIG_ENDIAN
  14 #define LE32(x) ((uint32_t)((((uint32_t)x)>>24) | ((((uint32_t)x)>>8) & 0xff00) | ((((uint32_t)x)<<8) & 0xff0000) | (((uint32_t)x)<<24)))
  15 #else
  16 #error BYTE_ORDER not defined/known!
  17 #endif
  18
  19 //Helper-routine: Convert a little-endian 4-byte word to an int
  20 static void int2chars(unsigned char *buff,unsigned int a) {
  21         buff[3]=(a>>24)&0xff;
  22         buff[2]=(a>>16)&0xff;
  23         buff[1]=(a>>8)&0xff;
  24         buff[0]=(a)&0xff;
  25 }
  26
  27 //Helper-routine: Convert an int to  little-endian 4-byte word
  28 unsigned int chars2int(unsigned char *buff) {
  29         unsigned int a;
  30         a=buff[3]<<24;
  31         a+=buff[2]<<16;
  32         a+=buff[1]<<8;
  33         a+=buff[0];
  34         return a;
  35 }
  36
  37 //This routine locates a scope by VID/PID and returns an opened handle to it.
  38 static usb_dev_handle *usbtmc_find_scope() {
  39         struct usb_bus *bus;
  40         struct usb_device *dev=NULL;
  41         usb_find_busses();
  42         usb_find_devices();
  43         for (bus=usb_busses; bus; bus=bus->next) {
  44                 for (dev=bus->devices; dev; dev=dev->next) {
  45                         //fprintf(stderr,"Prod/dev: %04X:%04X\n",dev->descriptor.idVendor,dev->descriptor.idProduct);
  46                         if (dev->descriptor.idVendor==0x400 && dev->descriptor.idProduct==0x5dc) {
  47                                 return usb_open(dev);
  48                         }
  49                 }
  50         }
  51         return NULL;
  52 }
  53
  54 //Send a scpi-command to the scope. The response goes into the buffer
  55 //called resp, with a size of resplen. If resp==NULL, no response
  56 //is requested.
  57 int usbtmc_sendscpi(usb_dev_handle *dev, char* cmd,
  58                 unsigned char *resp, int resplen) {
  59         unsigned char *buff;
  60         int len,r,i;
  61         int cmdlen = strlen(cmd);
  62         static unsigned char seq=0;
  63
  64
  65         buff=malloc(0x40);
  66         seq++;
  67         buff[0]=1; //func
  68         buff[1]=seq; buff[2]=~seq; //nseq
  69         buff[3]=0;
  70         int2chars(buff+4, cmdlen);
  71         buff[8]=1;
  72         buff[9]=0x00;
  73         buff[10]=0x00;
  74         buff[11]=0x00;
  75         //fprintf(stderr,"Writing header len=%d\n", cmdlen);
  76         //printb(buff,12);
  77         r=usb_bulk_write(dev, 1, (char*)buff, 12, USB_TIMEOUT);
  78         //fprintf(stderr,"%i bytes written. Writing cmd\n",r);
  79         //printb(cmd, cmdlen);
  80         r=usb_bulk_write(dev, 1, cmd, cmdlen, USB_TIMEOUT);
  81         //fprintf(stderr,"%i bytes written.\n",r);
  82         if (resp != NULL && resplen != 0) {
  83                 //send read command
  84                 buff[0]=2; //func
  85                 seq++;
  86                 buff[1]=seq; buff[2]=~seq; //nseq
  87                 int2chars(buff+4,0x40);
  88                 buff[8]=0;
  89                 buff[9]=0xA;
  90                 buff[10]=0;
  91                 buff[11]=0;
  92                 //fprintf(stderr,"Writing resp req header\n");
  93                 //printb(buff,12);
  94                 r=usb_bulk_write(dev, 1, (char*)buff, 12, USB_TIMEOUT);
  95                 //fprintf(stderr,"%i bytes written. Reading response hdr\n",r);
  96                 r=usb_bulk_read(dev, 2, (char*)buff, 0x40, USB_TIMEOUT);
  97                 //printb(buff,r);
  98                 len=chars2int(buff+4);
  99                 //fprintf(stderr,"%i bytes read. Resplen=%i\n",r,len);
 100                 for (i=0; i<(r-12); i++) {
 101                         if (i<resplen) resp[i] = buff[i+12];
 102                 }
 103                 //printb(resp,r-12);
 104                 if (len > 0x40-12) {
 105                         //fprintf(stderr," Reading response:\n");
 106                         if (resplen<len) len=resplen;
 107                         r=usb_bulk_read(dev, 2, (char*)resp+(0x40-12), len-(0x40-12), USB_TIMEOUT);
 108                         //fprintf(stderr,"%i bytes read, wanted %i.\n", r, len-(0x40-12));
 109                         return r+(0x40-12);
 110                 }
 111                 return len;
 112         }
 113         return 0;
 114 }
 115
 116 void usbtmc_claim(usb_dev_handle *sc)
 117 {
 118         usb_claim_interface(sc, 0);
 119 }
 120
 121 void usbtmc_release(usb_dev_handle *sc)
 122 {
 123         usb_release_interface(sc, 0);
 124 }
 125
 126 //Initialize the scope.
 127 usb_dev_handle* usbtmc_initscope(void) {
 128         int r;
 129         unsigned char buff[10];
 130         usb_dev_handle *dev;
 131
 132         //Init libusb
 133         usb_init();
 134         //Locate and open the scope
 135         dev = usbtmc_find_scope();
 136         if (!dev) {
 137                 return NULL;
 138         }
 139         usbtmc_claim(dev);
 140         //The following code isn't really necessary, the program works
 141         //OK without it too.
 142         r=usb_control_msg(dev, 0xC8, 9, 0, 0, (char*)buff, 4, USB_TIMEOUT);
 143         usbtmc_release(dev);
 144         if (r < 0) {
 145                 fprintf (stderr, "Error %d sending init message: %s\n",
 146                                 r, strerror (-r));
 147                 fprintf (stderr, "Do you have permission on the USB device?\n");
 148                 exit (1);
 149         }
 150         if (chars2int(buff)!=0x40005dc) {
 151                 fprintf(stderr,"Init: buff[%i]=%x\n",r,chars2int(buff));
 152         }
 153         return dev;
 154 }
 155
 156 void usbtmc_close(usb_dev_handle *sc)
 157 {
 158         //Free up and exit
 159         usb_close(sc);
 160 }