Page 4 of 13
Page 67
import fcntl
import struct
import io
GPIO_GET_CHIPINFO_IOCTL = 0x8044B401
f = io.open("/dev/gpiochip0", "rb", buffering=0)
gpiochip_info = struct.Struct("32s 32s L")
buffer = gpiochip_info.pack(b' ', b' ', 0)
result = fcntl.ioctl(f, GPIO_GET_CHIPINFO_IOCTL, buffer)
name, label, lines = gpiochip_info.unpack(result)
print(name.rstrip(b'\0').decode("utf-8"))
print(label.rstrip(b'\0').decode("utf-8"))
print(lines)
To run it on a Pi 5 change gpiochip0 to gpiochip4
Page 70
import fcntl
import struct
import io
GPIO_GET_CHIPINFO_IOCTL = 0x8044B401
GPIO_GET_LINEHANDLE_IOCTL = 0xC16CB403
GPIOHANDLE_SET_LINE_VALUES_IOCTL = 0xC040B409
GPIOHANDLE_GET_LINE_VALUES_IOCTL = 0xC040B408
GPIOHANDLE_REQUEST_OUTPUT = 0x02
GPIOHANDLE_REQUEST_INPUT = 0x01
GPIOHANDLE_REQUEST_ACTIVE_LOW = 0x04
GPIOHANDLE_REQUEST_OPEN_DRAIN = 0x08
GPIOHANDLE_REQUEST_OPEN_SOURCE = 0x10
gpiochip_info = struct.Struct("32s 32s L")
gpiohandle_request = struct.Struct("64L L 64B 32s L L")
gpiohandle_data = struct.Struct("64B")
lines = [0]*64
lines[0] = 4
lines[1] = 17
values = [0]*64
buffer = gpiohandle_request.pack(*lines, GPIOHANDLE_REQUEST_OUTPUT, *values, b"Output test", 2, 0)
f = io.open("/dev/gpiochip0", "rb", buffering=0)
result = fcntl.ioctl(f, GPIO_GET_LINEHANDLE_IOCTL, buffer)
f.close()
fL = struct.unpack_from("L", buffer, 360)[0]
values[0] = 1
values[1] = 0
state1 = gpiohandle_data.pack(*values)
values[0] = 0
values[1] = 1
state2 = gpiohandle_data.pack(*values)
while(True):
result = fcntl.ioctl(fL, GPIOHANDLE_SET_LINE_VALUES_IOCTL, state1)
result = fcntl.ioctl(fL, GPIOHANDLE_SET_LINE_VALUES_IOCTL, state2)
Remember to change gpiochip0 to gpiochip4 if you are running on a Pi 5.
Page 72
import fcntl
import struct
import io
import os
GPIO_GET_CHIPINFO_IOCTL = 0x8044B401
GPIO_GET_LINEHANDLE_IOCTL = 0xC16CB403
GPIOHANDLE_SET_LINE_VALUES_IOCTL = 0xC040B409
GPIOHANDLE_GET_LINE_VALUES_IOCTL = 0xC040B408
GPIOHANDLE_REQUEST_OUTPUT = 0x02
GPIOHANDLE_REQUEST_INPUT = 0x01
GPIOHANDLE_REQUEST_ACTIVE_LOW = 0x04
GPIOHANDLE_REQUEST_OPEN_DRAIN = 0x08
GPIOHANDLE_REQUEST_OPEN_SOURCE = 0x10
gpiochip_info = struct.Struct("32s 32s L")
gpiohandle_request = struct.Struct("64L L 64B 32s L L")
gpiohandle_data = struct.Struct("64B")
lines = [0]*64
lines[0] = 4
lines[1] = 17
values = [0]*64
buffer = gpiohandle_request.pack(*lines, GPIOHANDLE_REQUEST_INPUT, *values, b"Input test", 2, 0)
f = io.open("/dev/gpiochip0", "rb", buffering=0)
result = fcntl.ioctl(f, GPIO_GET_LINEHANDLE_IOCTL, buffer)
f.close()
fL = struct.unpack_from("L", result, 360)[0]
inputBuffer = gpiohandle_data.pack(*values)
result = fcntl.ioctl(fL, GPIOHANDLE_GET_LINE_VALUES_IOCTL, inputBuffer)
os.close(fL)
print(result[0], result[1])
Remember to change gpiochip0 to gpiochip4 if you are running on a Pi 5.
Page 73
import fcntl
import struct
import io
import os
from time import sleep, time_ns
GPIO_GET_CHIPINFO_IOCTL = 0x8044B401
GPIO_GET_LINEHANDLE_IOCTL = 0xC16CB403
GPIOHANDLE_SET_LINE_VALUES_IOCTL = 0xC040B409
GPIOHANDLE_GET_LINE_VALUES_IOCTL = 0xC040B408
GPIOHANDLE_REQUEST_OUTPUT = 0x02
GPIOHANDLE_REQUEST_INPUT = 0x01
GPIOHANDLE_REQUEST_ACTIVE_LOW = 0x04
GPIOHANDLE_REQUEST_OPEN_DRAIN = 0x08
GPIOHANDLE_REQUEST_OPEN_SOURCE = 0x10
gpiochip_info = struct.Struct("32s 32s L")
gpiohandle_request = struct.Struct("64L L 64B 32s L L")
gpiohandle_data = struct.Struct("64B")
lines = [0]*64
lines[0] = 4
values = [0]*64
buffer = gpiohandle_request.pack(*lines, GPIOHANDLE_REQUEST_INPUT,*values, b"Resistance test", 1, 0)
f = io.open("/dev/gpiochip0", "rb", buffering=0)
result = fcntl.ioctl(f, GPIO_GET_LINEHANDLE_IOCTL, buffer)
fL = struct.unpack_from("L", result, 360)[0]
state = gpiohandle_data.pack(*values)
result = fcntl.ioctl(fL, GPIOHANDLE_GET_LINE_VALUES_IOCTL, state)
sleep(0.01)
os.close(fL)
buffer = gpiohandle_request.pack(*lines, GPIOHANDLE_REQUEST_OUTPUT, *values, b"Resistance test", 1, 0)
result = fcntl.ioctl(f, GPIO_GET_LINEHANDLE_IOCTL, buffer)
fL = struct.unpack_from("L", result, 360)[0]
fcntl.ioctl(fL, GPIOHANDLE_SET_LINE_VALUES_IOCTL, state)
sleep(0.01)
os.close(fL)
buffer = gpiohandle_request.pack(*lines, GPIOHANDLE_REQUEST_INPUT,*values, b"Resistance test", 1, 0)
result = fcntl.ioctl(f, GPIO_GET_LINEHANDLE_IOCTL, buffer)
fL = struct.unpack_from("L", result, 360)[0]
t = time_ns()
result = fcntl.ioctl(fL, GPIOHANDLE_GET_LINE_VALUES_IOCTL, state)
while(result[0] == 0):
result = fcntl.ioctl(fL, GPIOHANDLE_GET_LINE_VALUES_IOCTL, state)
print((time_ns()-t)/1000)
os.close(fL)
f.close()
