Others/CHIP_IO
1
0
Fork 0
mirror of https://github.com/xtacocorex/CHIP_IO synced 2025-07-19 20:33:21 +00:00
Code Issues Releases Activity

Added the ability to read a full byte from a set of channels

Browse Source 
For example, you can hook up to the 8 XIO pins and 8 CSID pins to read
a word in just two calls: `GPIO.read_byte("XIO") + GPIO.read_byte("CSID") << 8`

For fast-changing inputs (e.g. reading from a counter), this is more
accurate than reading the bits individually.
This commit is contained in:
Brett van Zuiden
2017-01-29 12:32:53 -08:00
parent 2e2177da26
commit a498fc12bd
1 changed files with 53 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

53
source/py_gpio.c
View File

@ -290,6 +290,58 @@ static PyObject *py_input_gpio(PyObject *self, PyObject *args)
return py_value;
}
// python function value = read_byte(channel)
static PyObject *py_read_byte_gpio(PyObject *self, PyObject *args)
{
int gpio;
char *channel;
int i;
unsigned int bit;
unsigned int value = 0;
PyObject *py_value;
clear_error_msg();
if (!PyArg_ParseTuple(args, "s", &channel))
return NULL;
if (get_gpio_number(channel, &gpio)) {
}
if (strcmp(channel, "XIO") == 0) {
int base_gpio = get_xio_base();
for (i = 0; i < 8; i++) {
gpio = base_gpio + i;
if (gpio_get_value(gpio, &bit) < 0) {
char err[1024];
snprintf(err, sizeof(err), "Could not get bit ('%s')", get_error_msg());
PyErr_SetString(PyExc_RuntimeError, err);
return NULL;
}
value |= (bit << i);
}
} else if (strcmp(channel, "CSID") == 0) {
int base_gpio = 132;
for (i = 0; i < 8; i++) {
gpio = base_gpio + i;
if (gpio_get_value(gpio, &bit) < 0) {
char err[1024];
snprintf(err, sizeof(err), "Could not get bit ('%s')", get_error_msg());
PyErr_SetString(PyExc_RuntimeError, err);
return NULL;
}
value |= (bit << i);
}
} else {
PyErr_SetString(PyExc_ValueError, "Invalid channel");
return NULL;
}
py_value = Py_BuildValue("i", value);
return py_value;
}
static void run_py_callbacks(int gpio, void* data)
{
PyObject *result;
@ -860,6 +912,7 @@ PyMethodDef gpio_methods[] = {
{"cleanup", (PyCFunction)py_cleanup, METH_VARARGS | METH_KEYWORDS, "Clean up by resetting all GPIO channels that have been used by this program to INPUT with no pullup/pulldown and no event detection"},
{"output", py_output_gpio, METH_VARARGS, "Output to a GPIO channel\ngpio - gpio channel\nvalue - 0/1 or False/True or LOW/HIGH"},
{"input", py_input_gpio, METH_VARARGS, "Input from a GPIO channel. Returns HIGH=1=True or LOW=0=False\ngpio - gpio channel"},
{"read_byte", py_read_byte_gpio, METH_VARARGS, "Read a byte from a set of GPIO channels. Returns 8-bit integer\ngpio - gpio channel. Valid channels: 'XIO', 'CSID'"},
{"add_event_detect", (PyCFunction)py_add_event_detect, METH_VARARGS | METH_KEYWORDS, "Enable edge detection events for a particular GPIO channel.\nchannel - either board pin number or BCM number depending on which mode is set.\nedge - RISING, FALLING or BOTH\n[callback] - A callback function for the event (optional)\n[bouncetime] - Switch bounce timeout in ms for callback"},
{"remove_event_detect", py_remove_event_detect, METH_VARARGS, "Remove edge detection for a particular GPIO channel\ngpio - gpio channel"},
{"event_detected", py_event_detected, METH_VARARGS, "Returns True if an edge has occured on a given GPIO. You need to enable edge detection using add_event_detect() first.\ngpio - gpio channel"},