<div dir="ltr">Works fine following these steps:<div>0) Copied .fw firmware file from driver installed in Windows.<span style="background-color:rgb(245,249,253)"><br></span>1) Added my scanner to <i>/etc/sane.d/gt68xx.conf</i>:<blockquote style="margin:0 0 0 40px;border:none;padding:0px"><div><font face="monospace">...</font></div><div><font face="monospace"># Autodetect Xerox 7600</font></div><div><font face="monospace">usb 0x04a7 0x04a6</font></div><div><font face="monospace">override "plustek-opticslim-2400"</font></div></blockquote><div><font face="monospace"><br></font></div><div><font face="arial, sans-serif">For some reason, the scanner is idle for about 20 seconds before each scan, adjusting the exposure, so I had to hardcode some settings and remove the automatic adjustment of these parameters.</font><font face="monospace"><br></font></div><div>2) Commented lines <a href="https://gitlab.com/sane-project/backends/-/blob/master/backend/gt68xx_high.c#L1885">1885-1912</a> in sources (<i>sane-backends/backend/gt68xx_high.c</i>).<font face="monospace"><br></font></div>3) Commented lines <a href="https://gitlab.com/sane-project/backends/-/blob/master/backend/gt68xx_high.c#L1914">1917-1940</a> in the same file.</div><div><br><div><div>3) Added this code in the same file starting with line <a href="https://gitlab.com/sane-project/backends/-/blob/master/backend/gt68xx_high.c#L1914">1914</a>:<br></div><blockquote style="margin:0 0 0 40px;border:none;padding:0px"><font face="monospace">if (!red_done || !green_done || !blue_done)<br></font><font face="monospace">{<br></font><font face="monospace">    DBG (0, "gt68xx_afe_cis_auto: setting AFE reached limit\n");<br></font><span style="font-family:monospace">    </span><font face="monospace">DBG (0, "gt68xx_afe_cis_MOD: exposed custom values\n");<br></font><span style="font-family:monospace">    </span><b><font face="monospace">afe->r_offset = 13;<br></font><span style="font-family:monospace">    </span><font face="monospace">afe->g_offset = 15;<br></font><span style="font-family:monospace">    </span><font face="monospace">afe->b_offset = 16;<br></font><span style="font-family:monospace">    </span><font face="monospace">afe->r_pga = 3;<br></font><span style="font-family:monospace">    </span><font face="monospace">afe->g_pga = 4;<br></font><span style="font-family:monospace">    </span></b><font face="monospace"><b>afe->b_pga = 5;</b><br></font><span style="font-family:monospace">    </span><font face="monospace">gt68xx_afe_cis_adjust_gain_offset ("red", &values, r_obuffer, r_gbuffer, afe, &old_afe);<br></font><span style="font-family:monospace">    </span><font face="monospace">gt68xx_afe_cis_adjust_gain_offset ("green", &values, r_obuffer, r_gbuffer, afe, &old_afe);<br></font><span style="font-family:monospace">    </span><font face="monospace">gt68xx_afe_cis_adjust_gain_offset ("blue", &values, r_obuffer, r_gbuffer, afe, &old_afe);</font></blockquote><blockquote style="margin:0 0 0 40px;border:none;padding:0px"></blockquote></div></div><blockquote style="margin:0 0 0 40px;border:none;padding:0px"><div><div><span style="font-family:monospace">}</span></div></div></blockquote>4) Also commented the lines <a href="https://gitlab.com/sane-project/backends/-/blob/master/backend/gt68xx_high.c#L1946">1946-1952</a> (in the same file, of course) trying to save the settings (as I understand it, the program cannot do this, so the program adjusts them again every time ¯\_(ツ)_/¯ )</div>