Please find the simple settings as below:
Slackware workstation:
Assume that : wlan0 is the interface
Start-up script (manually)
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ifconfig wlan0 down; (off the interface too, not sure why my system required this)
iwconfig wlan0 mode ad-hoc;
iwconfig wlan0 essid islackware.blogspot.com;
iwconfig wlan0 channel 11;
iwconfig wlan0 key s:0123456789123;
dhcpcd wlan0;
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As for the mobile settings, pls refer to the attached.
After all this, ping 192.168.188.1 to see if there's any reply.
If you have any problem connecting it, feel free to leave comments..