Abbiamo già visto precedentemente come lavorare con i GPIO della raspberry, ma ecco il codice di una libreria che rende tutto più facile:
on Pi_gpio_init nbr dir
/* Pi_gpio_init RaspberryPi
Syntax:
Pi_gpio_init nbr, dir # Command #
Examples:
Pi_gpio_init 2, "in"
Pi_gpio_init 2, "out"
Description:
Initialize the gpio and set the direction of the operation
nbr is one of the gpio pins: "2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,32"
dir is "in" or "out"
Source:
Michael Doub
Pi_gpio_init */
/* Include
RaspberryPi_var
Pi_gpio_output
*/
local cmd, direction_path
if nbr is not among the items of good_pins then return "error: invalid pin nbr"
if lower(dir) is not among the items of good_directions then return "error: invalid direction"
if the platform is "Linux" then
put ("/sys/class/gpio/gpio" & nbr & "/direction") into direction_path
if there is not a file direction_path then
put "echo" && nbr && "> /sys/class/gpio/export" into cmd
get shell (cmd)
if it is not empty then return "error:" & it
end if
if there is not a file direction_path then return "error:" && direction_path && "does not exist"
open file direction_path for write
write dir to file direction_path
close file direction_path
end if
put dir into gpio[nbr][direction]
return empty
end Pi_gpio_init
on Pi_gpio_input nbr
/* Pi_gpio_input RaspberryPi
Syntax:
Pi_gpio_input nbr # Command #
Examples:
Pi_gpio_input 2
Description:
Input from the gpio nbr
nbr is one of the gpio pins: "2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,32"
Source:
Michael Doub
Pi_gpio_input */
/* Include
RaspberryPi_var
Pi_gpio_init
*/
local value_path
if nbr is not among the items of good_pins then return "error: invalid pin nbr"
if the platform is "Linux" then
put ("/sys/class/gpio/gpio" & nbr & "/value") into value_path
if there is not a file value_path then return "error:" && value_path && "does not exist"
open file value_path
read from file value_path until EOF
close file value_path
end if
return it
end Pi_gpio_input
on Pi_gpio_output nbr val
/* Pi_gpio_output RaspberryPi
Syntax:
Pi_gpio_output nbr, val # Command #
Examples:
Pi_gpio_output 2, 1
Pi_gpio_output 2, 0
Description:
Output to the gpio nbr, with value of val
nbr is one of the gpio pins: "2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,32"
val is 1 or 0
Source:
Michael Doub
Pi_gpio_output */
/* Include
RaspberryPi_var
Pi_gpio_init
*/
local value_path
if nbr is not among the items of good_pins then return "error: invalid pin nbr"
if val is not among the items good_values then return "error: invalid value"
if the platform is "Linux" then
put ("/sys/class/gpio/gpio" & nbr & "/value") into value_path
if there is not a file value_path then return "error:" && value_path && "does not exist"
open file value_path for write
write val to file value_path
close file value_path
end if
put val into gpio[nbr]["value"]
return empty
end Pi_gpio_output
on Pi_to_Gert_Close
/* Pi_to_Gert_Close RaspberryPi
Syntax:
Pi_to_Gert_Close # Command #
Examples:
Pi_to_Gert_Close
Description:
This reoutine actually closes the serial port to the GertDuino.
Source:
Michael Doub
Pi_to_Gert_Close */
/* Include
Pi_to_Gert_Variables
*/
put false into _pi_okToRead
wait for _pi_readrate with messages
close file _pi_thePort
end Pi_to_Gert_Close
on Pi_to_Gert_Open pPortName, pReadrate, pBaud, pParity, pDatabits, pStopbits
/* Pi_to_Gert_Open RaspberryPi
Syntax:
Pi_to_Gert_Open pPortName, [pReadrate], [pBaud], [pParity], [pDatabits], [pStopbits] # Command #
Examples:
Pi_to_Gert_Open
Description:
Set the serial port configuration paramenters and opens the serial port to the GertDuino.
Defaults:
. pPortName: "/dev/ttyAMA0"
. readrate: 10
. pBaud: 9600
. pParity: N
. pDatabits: 8
. pStopbits: 1
Source:
Michael Doub
Pi_to_Gert_Open */
/* Include
Pi_to_Gert_Variables
*/
if pPortName is empty then
put "/dev/ttyAMA0" into _pi_theport
else
put pPortName into _pi_thePort
end if
if pReadrate is empty then put 10 into _pi_readrate
if pBaud is empty then put 9600 into pBaud
if pParity is empty then put "N" into pParity
if pDatabits is empty then put 8 into pDatabits
if pStopbits is empty then put 1 into pStopbits
Put "BAUD=" & pBaud &&\
"PARITY="& pParity &&\
"DATA=" & pDatabits &&\
"STOP=" & pDatabits into serial
if the platform = "Linux" then
set the serialControlString to serial
open file _pi_thePort for binary update
end if
end Pi_to_Gert_Open
on Pi_to_Gert_Start_Reading pCallbackname, pObj
/* Pi_to_Gert_Start_Reading RaspberryPi
Syntax:
Pi_to_Gert_Start_Reading pCallbackname, pObj # Command #
Examples:
Pi_to_Gert_Start_Reading "WeGotData", me
Description:
This routine starts the reading process between the Gertduino and
the raspBerryPi. Since you must read the serial port until empty, this
means that you must constantly have a read active on the port.
When data is actually recieved it is passed
to pCallbackname of pObj thru the message path with a single parameter
of the data base64encoded.
Source:
Michael Doub
Pi_to_Gert_Start_Reading */
/* Include
Pi_to_Gert_Variables
readPort_Gert
*/
put true into _pi_okToRead
put pCallbackname into _pi_callbackname
put pObj into _pi_owner
readPort_Gert
end Pi_to_Gert_Start_Reading
on Pi_to_Gert_Stop_Reading
/* Pi_to_Gert_Stop_Reading RaspberryPi
Syntax:
Pi_to_Gert_Stop_Readingj # Command #
Examples:
Pi_to_Gert_Stop_Reading
Description:
This routine stops the continious read process that is expecting data
from the Gertdino serial port.
Source:
Michael Doub
Pi_to_Gert_Stop_Reading */
/* Include
Pi_to_Gert_Variables
*/
put false into _pi_okToRead
end Pi_to_Gert_Stop_Reading
on Pi_to_Gert_Write theData pDecode
/* Pi_to_Gert_Write RaspberryPi
Syntax:
Pi_to_Gert_Write theData, [pDecode] # Command #
Examples:
Pi_to_Gert_Write thedata
Pi_to_Gert_Write thedata, true
Description:
Writes theData to the Gertduino serial port. If pDecode is true then the data
will be base64decoded
Source:
Michael Doub
Pi_to_Gert_Write */
/* Include
Pi_to_Gert_Variables
*/
if pDecode then
write base64decode(theData) to file _pi_thePort
else
write theData to file _pi_thePort
end if
end Pi_to_Gert_Write
