ucecho.c File Reference

ucecho example for C. More...

Detailed Description

ucecho example for C.

This example demonstrates the usage of the C API and the low speed interface of default firmware.

The host software writes data to this interface, the FPGA converts it to uppercase and stores it such that it can be read back from the host through the low speed interface.

The correct bitstream is detected and found automatically if the binary is executed from the directory tree of the SDK. Otherwise it can be specified with parameter '-s'.

Full list of options can be obtained with '-h'

/*%
   ZTEX Core API for C with examples
   Copyright (C) 2009-2023 ZTEX GmbH.
   http://www.ztex.de
   
   This Source Code Form is subject to the terms of the Mozilla Public
   License, v. 2.0. If a copy of the MPL was not distributed with this file,
   You can obtain one at http://mozilla.org/MPL/2.0/.

   Alternatively, the contents of this file may be used under the terms
   of the GNU General Public License Version 3, as described below:

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 3 as
   published by the Free Software Foundation.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, see http://www.gnu.org/licenses/.
%*/

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <fcntl.h>
#include <libusb-1.0/libusb.h>

#include "ztex.h"

static char* prog_name = NULL;          // name of the programm

static int paramerr(const char* format,...)
{
    fprintf(stderr, "Usage: %s options\n",prog_name);
    fprintf(stderr, "  -h                           Display this usage information\n"
                    "  -fu <vendor ID>:<product ID> Select device by USB IDs, default: 0x221A:0x100, <0:ignore ID\n"
                    "  -fd <bus>:<device>           Select device by bus number and device address\n"
                    "  -fs <string>                 Select device by serial number string\n"
                    "  -fp <string>                 Select device by product string\n"
                    "  -s <path>                    Addtional search path for bitstream, default '.."DIRSEP".."DIRSEP"examples"DIRSEP"ucecho'\n"
                    "  -r                           Reset device (default: reset configuration only)\n"
                    "  -i                           Print device info\n"
                    "  -p                           Print matching USB devices\n"
                    "  -pa                          Print all USB devices\n"
            );
    if ( format ) {
        va_list args;
        va_start(args,format);
        vfprintf(stderr, format, args);
        va_end(args);
        return 1;
    }
    return 0;
}

int main(int argc, char **argv)
{
    int id_vendor = 0x221A;     // ZTEX vendor ID
    int id_product = 0x100;     // default product ID for ZTEX firmware
    int status = 0;
    libusb_device **devs = NULL;
    int print_all=0, print=0, print_info=0, reset_dev=0;
    int busnum = -1, devnum = -1;
    char *sn_string = NULL, *product_string = NULL;
    libusb_device_handle *handle = NULL;
    ztex_device_info info;
    char *bitstream_fn = NULL, *bitstream_path = NULL;
    char sbuf[8192];
    uint8_t cbuf[1024];
    uint32_t vbuf[256];
    int vlen,slen;

    prog_name = argv[0];
    for (int i=1; i<argc; i++) {
        if ( !strcmp(argv[i],"-h") ) return paramerr(NULL);
        else if ( !strcmp(argv[i],"-p") ) print=1;
        else if ( !strcmp(argv[i],"-pa") ) print_all=1;
        else if ( !strcmp(argv[i],"-i") ) print_info=1;
        else if ( !strcmp(argv[i],"-r") ) reset_dev=1;
        else if ( !strcmp(argv[i],"-fu") ) {
            i++;
            if (i>=argc || sscanf(argv[i],"%i:%i", &id_vendor, &id_product)!=2 ) return paramerr("Error: <vendor ID>:<product ID> expected after -fu\n");
        }
        else if ( !strcmp(argv[i],"-fd") ) {
            i++;
            if (i>=argc || sscanf(argv[i],"%i:%i", &busnum, &devnum)!=2 ) return paramerr("Error: <bus>:<device> expected after -fd\n");
        }
        else if ( !strcmp(argv[i],"-fs") ) {
            i++;
            if (i>=argc ) return paramerr("Error: <string> expected after -fs\n");
            sn_string = argv[i];
        }
        else if ( !strcmp(argv[i],"-fp") ) {
            i++;
            if (i>=argc ) return paramerr("Error: <string> expected after -fp\n");
            product_string = argv[i];
        }
        else if ( !strcmp(argv[i],"-s") ) {
            i++;
            if (i>=argc ) return paramerr("Error: <path> expected after -s\n");
            bitstream_path = argv[i];
        }
        else return paramerr("Error: Invalid parameter %s\n", argv[i]);
    }

    // INIT libusb
    status = libusb_init(NULL);
    if (status < 0) {
        fprintf(stderr,"Error: Unable to init libusb: %s\n", libusb_error_name(status));
        return 1;
    }

    // find all USB devices
    status = libusb_get_device_list(NULL, &devs);
    if (status < 0) {
        fprintf(stderr,"Error: Unable to get device list: %s\n", libusb_error_name(status));
        goto err;
    }
    
    // print bus info or find device
    int dev_idx = ztex_scan_bus(sbuf, sizeof(sbuf), devs, print_all ? -1 : print ? 1 : 0, id_vendor, id_product, busnum, devnum, sn_string, product_string);
    printf(sbuf);
    if ( print || print_all ) {
        status = 0;
        goto noerr;
    } else if ( dev_idx<0 ) {
        if (dev_idx==-1) fprintf(stderr,"Error: No device found\n");
        goto err;
    }

    // open device
    status = libusb_open(devs[dev_idx], &handle);
    if (status < 0) {
        fprintf(stderr,"Error: Unable to open device: %s\n", libusb_error_name(status));
        goto err;
    }
    libusb_free_device_list(devs, 1);
    devs=NULL;
    libusb_set_configuration(handle,1);
    
    // reset configuration or device
   if ( ! reset_dev ) {
        status = libusb_set_configuration(handle,-1);
        if (status < 0) {
            fprintf(stderr,"Warning: Unable to unconfigure device: %s, trying to reset it\n", libusb_error_name(status));
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
            fprintf(stderr,"Due to limitations of Windows neither this nor device reset works. This may cause further errors ...\n");
#endif    
            reset_dev = 1;
        }
    }
    if ( reset_dev ) {
        status = libusb_reset_device(handle);
        if (status < 0) {
            fprintf(stderr,"Error: Unable to reset device: %s\n", libusb_error_name(status));
            goto err;
        }
    }
    status = libusb_set_configuration(handle,1);
    if (status < 0) fprintf(stderr,"Warning: Unable to set configuration 1: %s\n", libusb_error_name(status));
    fflush(stderr);

    
    // get and print device info
    status = ztex_get_device_info(handle, &info);
    if ( status < 0 ) {
        fprintf(stderr,"Error: Unable to get device info: %s\n", libusb_error_name(status));
        goto err;
    }
    if ( print_info ) {
        ztex_print_device_info( sbuf, sizeof(sbuf), &info );
        printf(sbuf);
        status = ztex_get_fpga_config(handle);
        if ( status < 0 ) {
            fprintf(stderr,"Error: Unable to get FPGA configuration state: %s\n", libusb_error_name(status));
            goto err;
        }
        printf("FPGA: %s\n", status==0 ? "unconfigured" : "configured");
        status = 0;
        goto noerr;
    }
    fflush(stderr);
    
    // find bitstream
    bitstream_fn = ztex_find_bitstream( &info, bitstream_path ? bitstream_path : ".."DIRSEP".."DIRSEP"examples"DIRSEP"ucecho" , "ucecho");
    if ( bitstream_fn )  {
        printf("Using bitstream '%s'\n", bitstream_fn);
        fflush(stdout);
    }
    else {
        fprintf(stderr,"Warning: Bitstream not found\n");
        goto nobitstream;
    }
    
    // read and upload bitstream
    FILE *fd = fopen(bitstream_fn, "rb");
    if ( fd == NULL ) {
        fprintf(stderr,"Warning: Error opening file '%s'\n", bitstream_fn);
        goto nobitstream;
    }
    status = ztex_upload_bitstream(sbuf,sizeof(sbuf),handle,&info,fd,-1);
    fclose(fd);
    fprintf(stderr,sbuf);
    
nobitstream:
    fflush(stderr);
    status = ztex_get_fpga_config(handle);
    if ( status < 0 ) {
        fprintf(stderr,"Error: Unable to get FPGA configuration state: %s\n", libusb_error_name(status));
        goto err;
    } else if ( status == 0 ) {
        fprintf(stderr,"Error: FPGA not configured\n");
        goto err;
    }

    // ucecho test
    sbuf[0]=0;
    while ( strcmp(sbuf,"quit") ) {
        printf("Enter a string or `quit' to exit the program: ");
        fflush(stdout);
        fgets(sbuf, sizeof(sbuf)-1, stdin);
        slen = strlen(sbuf);
        while ( (slen>0) && (sbuf[slen-1]<32) ) slen--;
        sbuf[slen]=0; 
        if ( sbuf[0] ) {
            vlen = (slen+3)>>2;
            if ( vlen > 256 ) vlen = 256;
            memcpy(cbuf, sbuf, vlen*4);
            for (int i=0; i<vlen*4; i++) 
                vbuf[i] = cbuf[i*4+0] | (cbuf[i*4+1]<<8) | (cbuf[i*4+2]<<16) | (cbuf[i*4+3]<<24);
            printf("Send %d words to address 10 ...\n",vlen);
            status = ztex_default_lsi_set2(handle,10,vbuf,vlen);
            if ( status<0 ) {
                fprintf(stderr,"Warning: Error writing to LSI: %s\n", strerror(status));
                goto err;
            }
            
            status = ztex_default_lsi_get2(handle,10,vbuf,vlen);
            if ( status<0 ) {
                fprintf(stderr,"Warning: Error reading from to LSI: %s\n", strerror(status));
                goto err;
            }
            for (int i=0; i<vlen; i++) {
                cbuf[i*4+0] = vbuf[i];
                cbuf[i*4+1] = vbuf[i]>>8;
                cbuf[i*4+2] = vbuf[i]>>16;
                cbuf[i*4+3] = vbuf[i]>>24;
            }
            cbuf[slen]=0;
            printf("Read %d words starting from 10: %s\n", vlen, cbuf );  
            
            if ( vlen>1 ) {
                status = ztex_default_lsi_get2(handle,11,vbuf,vlen);
                if ( status<0 ) {
                    fprintf(stderr,"Warning: Error reading from to LSI: %s\n", strerror(status));
                    goto err;
                }
                for (int i=0; i<vlen; i++) {
                    cbuf[i*4+0] = vbuf[i];
                    cbuf[i*4+1] = vbuf[i]>>8;
                    cbuf[i*4+2] = vbuf[i]>>16;
                    cbuf[i*4+3] = vbuf[i]>>24;
                }
                cbuf[slen-4]=0;
                printf("Read %d words starting from 11: %s\n", vlen-1, cbuf );  
            }
        }
        printf("\n");
    }

    // release resources
    status = 0;
    goto noerr;
err:
    status = 1;
noerr:
    if ( bitstream_fn ) free(bitstream_fn);
    if ( handle ) libusb_close(handle);
    if ( devs ) libusb_free_device_list(devs, 1);
    libusb_exit(NULL);
#if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
    if ( strcmp(sbuf,"quit") ) {
        printf("Press <return> to quit\n");
        fflush(NULL);
        fgetc(stdin);
    }   
#endif    
    return status;
}