Tcl Raspberry Pi I/O


The onewire command


package require onewire

onewire subcommand ?arg ...?


The onewire command lets you interact with DS2482 based devices. Both the DS2482-100, driving a single 1-wire interface, and the DS2482-800 driving 8 1-wire interfaces, can be used. The legal values of subcommand are listed below. Note that you can abbreviate the subcommands.

onewire ds2482 bus ?number?
Open a channel to a DS2482 device. There can be up to four DS2482-100 devices, or up to eight DS2482-800 devices on the same i2c bus. The number argument selects which of the devices to access. The command returns the channel handle.
onewire configure handle ?option ...?
Configure the 1-wire interface options. All specified options will be enabled, while unspecified options are disabled. Valid options are:
  • APU - Active pull-up
  • SPU - Strong pull-up
  • 1WS - Overdrive speed
onewire channel handle channel
Select which of the 8 1-wire channels to access. This is only applicable for DS2482-800 devices.
onewire inventory handle
Find the addresses of all 1-wire devices on the 1-wire bus. The addresses are returned as a list, where each device is a list of 8 bytes expressed in decimal.
onewire convert handle ?device?
Instruct one or all temperature sensors on the 1-wire bus to start a temperature conversion.
onewire temperature handle ?device?
Read the result of the last temperature conversion. The device argument may only be omitted if there is exactly one 1-wire device connected on the bus. This command supports both DS18S20 and DS18B20 temperature sensors.