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diff --git a/apps/system/i2c/README.txt b/apps/system/i2c/README.txt deleted file mode 100644 index 7b432533b..000000000 --- a/apps/system/i2c/README.txt +++ /dev/null @@ -1,397 +0,0 @@ -README File for the I2C Tool
-============================
-
-The I2C tool provides a way to debug I2C related problems. This README file
-will provide usage information for the I2C tools.
-
-CONTENTS
-========
-
- o System Requirements
- - I2C Driver
- - Configuration Options
- o Help
- o Common Line Form
- o Common Command Options
- - "Sticky" Options
- - Environment variables
- - Common Option Summary
- o Command summary
- - bus
- - dev
- - get
- - set
- - verf
- o I2C Build Configuration
- - NuttX Configuration Requirements
- - I2C Tool Configuration Options
-
-System Requirements
-===================
-
-I2C Driver
-----------
-In order to use the I2C driver, you system -- in particular, your I2C driver --
-must meet certain requirements:
-
-1. It support calling up_i2cinitialize() numerous times, resetting the I2C
- hardware on each (initial) time. up_i2cuninitialize() will be called after
- each call to up_i2cinitialize() to free any resources and disable the I2C.
-2. up_i2cinitialize must accept any interface number without crashing. It
- must simply return NULL if the device is not supported.
-3. The I2C driver must support the transfer method (CONFIG_I2C_TRANSFER=y).
-
-The I2C tool is designed to be implemented as a NuttShell (NSH) add-on. Read
-the apps/nshlib/README.txt file for information about add-ons.
-
-Configuration Options
----------------------
-CONFIG_I2CTOOL_BUILTIN - Build the tools as an NSH built-in command
-CONFIG_I2CTOOL_MINBUS - Smallest bus index supported by the hardware (default 0).
-CONFIG_I2CTOOL_MAXBUS - Largest bus index supported by the hardware (default 3)
-CONFIG_I2CTOOL_MINADDR - Minium device address (default: 0x03)
-CONFIG_I2CTOOL_MAXADDR - Largest device address (default: 0x77)
-CONFIG_I2CTOOL_MAXREGADDR - Largest register address (default: 0xff)
-CONFIG_I2CTOOL_DEFFREQ - Default frequency (default: 4000000)
-
-HELP
-====
-
-First of all, the I2C tools supports a pretty extensive help output. That
-help output can be view by entering either:
-
- nsh> i2c help
-
-or
-
- nsh> i2c ?
-
-Here is an example of the help output. I shows the general form of the
-command line, the various I2C commands supported with their unique command
-line options, and a more detailed summary of the command I2C command
-options.
-
- nsh> i2c help
- Usage: i2c <cmd> [arguments]
- Where <cmd> is one of:
-
- Show help : ?
- List buses : bus
- List devices : dev [OPTIONS] <first> <last>
- Read register : get [OPTIONS] [<repititions>]
- Show help : help
- Write register: set [OPTIONS] <value> [<repititions>]
- Verify access : verf [OPTIONS] <value> [<repititions>]
-
- Where common "sticky" OPTIONS include:
- [-a addr] is the I2C device address (hex). Default: 03 Current: 03
- [-b bus] is the I2C bus number (decimal). Default: 1 Current: 1
- [-r regaddr] is the I2C device register address (hex). Default: 00 Current: 00
- [-w width] is the data width (8 or 16 decimal). Default: 8 Current: 8
- [-s|n], send/don't send start between command and data. Default: -n Current: -n
- [-i|j], Auto increment|don't increment regaddr on repititions. Default: NO Current: NO
- [-f freq] I2C frequency. Default: 100000 Current: 100000
-
- NOTES:
- o An environment variable like $PATH may be used for any argument.
- o Arguments are "sticky". For example, once the I2C address is
- specified, that address will be re-used until it is changed.
-
- WARNING:
- o The I2C dev command may have bad side effects on your I2C devices.
- Use only at your own risk.
-
-COMMAND LINE FORM
-=================
-
-The I2C is started from NSH by invoking the 'i2c' command from the NSH
-command line. The general form of the 'i2c' command is:
-
- i2c <cmd> [arguments]
-
-Where <cmd> is a "sub-command" and identifies one I2C operations supported
-by the tool. [arguments] represents the list of arguments needed to perform
-the I2C operation. Those arguments vary from command to command as
-described below. However, there is also a core set of common OPTIONS
-supported by all commands. So perhaps a better representation of the
-general I2C command would be:
-
- i2c <cmd> [OPTIONS] [arguments]
-
-Where [OPTIONS] represents the common options and and arguments represent
-the operation-specific arguments.
-
-COMMON COMMAND OPTIONS
-======================
-
-"Sticky" Options
-----------------
-In order to interact with I2C devices, there are a number of I2C parameters
-that must be set correctly. One way to do this would be to provide to set
-the value of each separate command for each I2C parameter. The I2C tool
-takes a different approach, instead: The I2C configuration can be specified
-as a (potentially long) sequence of command line arguments.
-
-These arguments, however, are "sticky." They are sticky in the sense that
-once you set the I2C parameter, that value will remain until it is reset
-with a new value (or until you reset the board).
-
-Environment Variables
----------------------
-NOTE also that if environment variables are not disabled (by
-CONFIG_DISABLE_ENVIRON=y), then these options may also be environment
-variables. Environment variables must be preceded with the special
-character $. For example, PWD is the variable that holds the current
-working directory and so $PWD could be used as a command line argument. The
-use of environment variables on the I2C tools command is really only useful
-if you wish to write NSH scripts to execute a longer, more complex series of
-I2C commands.
-
-Common Option Summary
----------------------
-
-[-a addr] is the I2C device address (hex). Default: 03 Current: 03
-
- The [-a addr] sets the I2C device address. The valid range is 0x03
- through 0x77 (this valid range is controlled by the configuration settings
- CONFIG_I2CTOOL_MINADDR and CONFIG_I2CTOOL_MAXADDR). If you are working
- with the same device, the address needs to be set only once.
-
- All I2C address are 7-bit, hexadecimal values.
-
- NOTE 1: Notice in the "help" output above it shows both default value of
- the I2C address (03 hex) and the current address value (also 03 hex).
-
- NOTE 2: Sometimes I2C addresses are represented as 8-bit values (with
- bit zero indicating a read or write operation). The I2C tool uses a
- 7-bit representation of the address with bit 7 unused and no read/write
- indication in bit 0. Essentially, the 7-bit address is like the 8-bit
- address shifted right by 1.
-
- NOTE 3: Most I2C bus controllers will also support 10-bit addressing.
- That capability has not been integrated into the I2C tool as of this
- writing.
-
-[-b bus] is the I2C bus number (decimal). Default: 1 Current: 1
-
- Most devices support multiple I2C devices and also have unique bus
- numbering. This option identifies which bus you are working with now.
- The valid range of bus numbers is controlled by the configuration settings
- CONFIG_I2CTOOL_MINBUS and CONFIG_I2CTOOL_MAXBUS.
-
- The bus numbers are small, decimal numbers.
-
-[-r regaddr] is the I2C device register address (hex). Default: 00 Current: 00
-
- The I2C set and get commands will access registers on the I2C device. This
- option selects the device register address (sometimes called the sub-address).
- This is an 8-bit hexadecimal value. The maximum value is determined by
- the configuration setting CONFIG_I2CTOOL_MAXREGADDR.
-
-[-w width] is the data width (8 or 16 decimal). Default: 8 Current: 8
-
- Device register data may be 8-bit or 16-bit. This options selects one of
- those two data widths.
-
-[-s|n], send/don't send start between command and data. Default: -n Current: -n
-
- This determines whether or not there should be a new I2C START between
- sending of the register address and sending/receiving of the register data.
-
-[-i|j], Auto increment|don't increment regaddr on repititions. Default: NO Current: NO
-
- On commands that take a optional number of repetitions, the option can be
- used to temporarily increment the regaddr value by one on each repitition.
-
-[-f freq] I2C frequency. Default: 400000 Current: 400000
-
- The [-f freq] sets the frequency of the I2C device.
-
-COMMAND SUMMARY
-===============
-
-We have already seen the I2C help (or ?) commands above. This section will
-discuss the remaining commands.
-
-List buses: bus [OPTIONS]
---------------------------
-
-This command will simply list all of the configured I2C buses and indicate
-which are supported by the driver and which are not:
-
- BUS EXISTS?
- Bus 1: YES
- Bus 2: NO
-
-The valid range of bus numbers is controlled by the configuration settings
-CONFIG_I2CTOOL_MINBUS and CONFIG_I2CTOOL_MAXBUS.
-
-List devices: dev [OPTIONS] <first> <last>
-------------------------------------------
-
-The 'dev' command will attempt to identify all of the I2C devices on the
-selected bus. The <first> and <last> arguments are 7-bit, hexadecimal
-I2C addresses. This command will examine a range of addresses beginning
-with <first> and continuing through <last>. It will request the value
-of register zero from each device.
-
-If the device at an address responds, then this command will display the
-address of the device. If the device does not respond, this command will
-display "--". The resulting display is like:
-
-nsh> i2c dev 03 77
- 0 1 2 3 4 5 6 7 8 9 a b c d e f
-00: -- -- -- -- -- -- -- -- -- -- -- -- --
-10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-40: -- -- -- -- -- -- -- -- -- 49 -- -- -- -- -- --
-50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
-70: -- -- -- -- -- -- -- --
-
-WARNINGS:
- o The I2C dev command may have bad side effects on certain I2C devices.
- For example, if could cause data loss in an EEPROM device.
- o The I2C dev command also depends upon the underlying behavior of the
- I2C driver. How does the driver respond to addressing failures?
-
-Read register: get [OPTIONS]
-----------------------------
-
- This command will read the value of the I2C register using the selected
- I2C parameters in the common options. No other arguments are required.
-
- This command with write the 8-bit address value then read an 8- or 16-bit
- data value from the device. Optionally, it may re-start the transfer
- before obtaining the data.
-
- An optional <repititions> argument can be supplied to repeat the
- read operation an arbitrary number of times (up to 2 billion). If
- auto-increment is select (-i), then the register address will be
- temporarily incremented on each repitions. The increment is temporary
- in the since that it will not alter the "sticky" value of the
- register address.
-
- On success, the output will look like the following (the data value
- read will be shown as a 4-character hexadecimal number if the 16-bit
- data width option is selected).
-
- READ Bus: 1 Addr: 49 Subaddr: 04 Value: 96
-
- All values (except the bus numbers) are hexadecimal.
-
-Write register: set [OPTIONS] <value>
--------------------------------------
-
- This command will write a value to an I2C register using the selected
- I2C parameters in the common options. The value to write must be provided
- as the final, hexadecimal value. This value may be an 8-bit value (in the
- range 00-ff) or a 16-bit value (in the range 0000-ffff), depending upon
- the selected data width.
-
- This command will write the 8-bit address value then write the 8- or 16-bit
- data value to the device. Optionally, it may re-start the transfer
- before writing the data.
-
- An optional <repititions> argument can be supplied to repeat the
- write operation an arbitrary number of times (up to 2 billion). If
- auto-increment is select (-i), then the register address will be
- temporarily incremented on each repitions. The increment is temporary
- in the since that it will not alter the "sticky" value of the
- register address.
-
- On success, the output will look like the following (the data value
- written will be shown as a 4-character hexadecimal number if the 16-bit
- data width option is selected).
-
- WROTE Bus: 1 Addr: 49 Subaddr: 04 Value: 96
-
- All values (except the bus numbers) are hexadecimal.
-
-Verify access : verf [OPTIONS] <value> [<repititions>]
-------------------------------------------------------
-
- This command combines writing and reading from an I2C device register.
- It will write a value to an will write a value to an I2C register using
- the selected I2C parameters in the common options just as described for
- tie 'set' command. Then this command will read the value back just
- as described with the 'get' command. Finally, this command will compare
- the value read and against the value written and emit an error message
- if they do not match.
-
- If no value is provided, then this command will use the register address
- itself as the data, providing for a address-in-address test.
-
- An optional <repititions> argument can be supplied to repeat the
- verify operation an arbitrary number of times (up to 2 billion). If
- auto-increment is select (-i), then the register address will be
- temporarily incremented on each repitions. The increment is temporary
- in the since that it will not alter the "sticky" value of the
- register address.
-
- On success, the output will look like the following (the data value
- written will be shown as a 4-character hexadecimal number if the 16-bit
- data width option is selected).
-
- VERIFY Bus: 1 Addr: 49 Subaddr: 04 Wrote: 96 Read: 92 FAILURE
-
- All values (except the bus numbers) are hexadecimal.
-
-I2C BUILD CONFIGURATION
-=======================
-
-NuttX Configuration Requirements
---------------------------------
-The I2C tools requires the following in your NuttX configuration:
-
-1. Device-specific I2C support must be enabled. The I2C tool will call the
- platform-specific function up_i2cinitialize() to get instances of the
- I2C interface and the platform-specific function up_i2cuninitialize()
- to discard instances of the I2C interface.
-
- NOTE 1: The I2C interface is defined in include/nuttx/i2c.h.
-
- NOTE 2: This I2C tool uses direct I2C device interfaces. As such, it
- relies on internal OS interfaces that are not normally available to a
- user-space program. As a result, the I2C tool cannot be used if a
- NuttX is built as a protected, supervisor kernel (CONFIG_NUTTX_KERNEL).
-
-2. I2C driver configuration
-
- The CONFIG_I2C_TRANSFER option must also be set in your NuttX
- configuration. This configuration is the defconfig file in your
- configuration directory that is copied to the NuttX top-level
- directory as .config when NuttX is configured.
-
- CONFIG_I2C_TRANSFER=y
-
- NOTE: CONFIG_I2C_TRANSFER adds extra methods to the I2C interface.
- Not all I2C interfaces support these extra methods. If your platform's
- I2C driver does not support these extra methods, then you cannot use
- the I2C tool unless you extend the support in your platform I2C
- driver.
-
-3. Application configuration.
-
- The path to the I2C tool directory must also be set in your NuttX
- application configuration. This application configuration is the
- appconfig file in your configuration directory that is copied to the
- NuttX application directory as .config when NuttX is configured.
-
- CONFIGURE_APPS += system/i2c
-
-I2C Tool Configuration Options
-------------------------------
-
-The default behavior of the I2C tool can be modified by the setting the
-options in the NuttX configuration. This configuration is the defconfig
-file in your configuration directory that is copied to the NuttX top-level
-directory as .config when NuttX is configured.
-
- CONFIG_I2CTOOL_BUILTIN: Build the tools as an NSH built-in command
- CONFIG_I2CTOOL_MINBUS: Smallest bus index supported by the hardware (default 0).
- CONFIG_I2CTOOL_MAXBUS: Largest bus index supported by the hardware (default 3)
- CONFIG_I2CTOOL_MINADDR: Minium device address (default: 0x03)
- CONFIG_I2CTOOL_MAXADDR: Largest device address (default: 0x77)
- CONFIG_I2CTOOL_MAXREGADDR: Largest register address (default: 0xff)
- CONFIG_I2CTOOL_DEFFREQ: Default frequency (default: 4000000)
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