= Device Drivers =

== Overview ==
For testing some device drivers may be loaded or unloaded dynamically or a startup script may be used to automatically load the modules.

||'''Driver'''||'''Module Filename'''||'''Device Nodes'''||'''Depends on other modules'''||
||Mainboard communications||mnbd-comm.ko||/dev/mnbd[[BR]]/dev/wt1 ..[[BR]][[BR]]/dev/wt10||||
||USB Hub||isp1520.ko||||i2c-mcf, i2c-core||
||Keypad/Beeper||max734x.ko||/dev/cardbeep||I2c-mcf, i2c-core||

Device driver operation may be tested from command line for some functions, for example:

{{{
# echo “A,B,C” > /dev/cardbeep <CR>
}}}
Play notes A, B, and C on beeper. ''(refer to beeper section for more details)''

{{{
# echo “W” > /dev/wt1 <CR>
}}}
Request weight from scale one.

{{{
# cat < /dev/wt1 <CR>
}}}
Display response to previous request from scale 1 as a weight structure converted to hexadecimal.

{{{
#!c
01004812B682000000004812B6820003

struct mnbd_wt_struct
{
  unsigned char interval;          (01 – interval 1)
  unsigned char decimal;           (00 – no decimal)
  float grosswt;                   (4812B682 – IEEE floating point value)
  float tarewt;                    (00000000 – IEEE floating point value–tare zero)
  float netwt;                     (4812B682 – IEEE floating point value)
  unsigned char units;             (00 – units)
  unsigned char status;            (03 – status)
};
}}}