gce8: Control a GCE Electronics USB 8 relays card
In EcoNum/econum: Various Tools Developed at EcoNum Lab

Description Usage Arguments Value Note Author(s) See Also Examples

Switch individual channels on or off in the USB interface card, or read its current state.

gce8_port(port = getOption("gce8_port"), name)

gce8_name(port = gce8_port())

gce8_relays(names, port = gce8_port(), name = gce8_name(port))

gce8_list()

gce8_open(port = gce8_port(), name = gce8_name(port))

gce8_close(port = gce8_port(), name = gce8_name(port))

gce8_ready(port = gce8_port(), name = gce8_name(port))

gce8_cmd(relay, on = TRUE, port = gce8_port(), name = gce8_name(port))

gce8_get(port = gce8_port(), name = gce8_name(port))

gce8_set(state = FALSE, port = gce8_port(), name = gce8_name(port))

`port`	The comm port to use (this is a virtual comm port using the FTDI virtual port driver available for Windows, Mac OS and Linux). If a number (x) is provided, the port is assumed to be 'comx', which is only a valid assuption under Windows. Use fully qualified name on Linux or Mac).
`name`	The name of the device. With `gce8_port()` it is used to retrieve the corresponding port; with `gce8_open()`, it forces the name of the card to use in R.
`names`	A vector of eight character strings to use to define the name of the eight relays. Missing data represent unused relays.
`relay`	The number, or name of the relay to switch.
`on`	Do we switch the relay on or off? Can be a boolean, 0/1 or "0"/"1".
`state`	The state of the relays. Can be a vector of eight items (otherwise, recycling rule applies), either boolean, integers 0/1, or anything that automatically coerces into boolean. Missing values are accepted and they will match relay that are not modified. The vector can also be named, and in this case, names will be match to the names used for the 8 relays: R1-R8, or anything else specified using `gce8_relays()`.'

Most functions return TRUE in case of success and FALSE or a try-error object in case of failure., except:

gce8_port() and gce8_name() return the port and name of a card,

gce8_list() returns the list of currently connected cards,

gce8_relays() returns a vector of eight character strings with the name of the eight relays (dot . substituted for missing values)

gce8_get() returns a named vector of eight booleans indicating the state of the eight relays. Names are the current names of the relays, or the default names R1-R8.

Functions gce8_cmd(), gce8_get() and gce8_set() functions use a mechanism to reconnect in case of lost connection. For instance, if the USB cord is unplugged and plugged again, connection is lost, but these functions can recover it. It only takes about 1 sec more to replug the card. If you forgot to connect with gce8_open(), these functions will do this automatically for you. However, you should always use gce8_close() once you have done with the card, in order to free the comm port handle. This will works too if the main power of the card in shut off and on again, but take care that all relays do return in off state and your program is not necessarily aware of that situation, unless you use gce8_get(). For critical applications, do prefer using gce8_set() and always specify all eight relays state instead of using gce8_cmd().

Those cards come from GCE Electronics.

Philippe Grosjean Philippe.Grosjean@umons.ac.be

wtw_open(), iks_open()

## Not run: 
# If the USB interface card is connected to com5, this should work:
options(gce8_port = 5)
# On the Mac, use: options(gce8_port = "/dev/cu.usbserial-A4003CDu")
gce8_open() # Note that this is facultative, since I connect on first use!
gce8_cmd(5, 1)
gce8_get()
gce8_set(FALSE)
gce8_close() # On the other hand, this is required to free the port!

## End(Not run)