diff --git a/industry/abnt_codi/README.md b/industry/abnt_codi/README.md
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-# Industry / `abnt_codi` ABNT CODI
-
-The ABNT CODI is an old energy meter standard used in Brazil.
-
-This code interprets the end user serial output existent in the energy meter.
-That output externalizes its data blinking an LED as a serial protocol at the
-baudrate of `110 BPS` and uses `8` octects:
-
-| Octet | Bits | Description
-|:-----:|------:|-------------
-| `001` | `0-7` | Number of seconds to the end of current active demand (`LSB`)
-| `002` | `0-3` | Number of seconds to the end of current active demand (`MSB`)
-| | `4` | Bill indicator. It is inverted at each demand replenishment
-| | `5` | Reactive Interval Indicator. Inverted at end react interval
-| | `6` | If `1` means the reactive-capacitive is used to calculate `UFER`
-| | `7` | If `1` means the reactive-inductive is used to calculate `UFER`
-| `003` | `0-3` | Current seasonal segment:
`0001` – tip
`0010` – out of tip
`1000` – reserved
-| | `4-5` | Type of charging indicator (flag):
`00` – Blue
`01` – Green
`10` – Irrigators
`11` – Other
-| | `6` | Not used
-| | `7` | If equal `1` means reactive rate is enabled
-| `004` | `0-7` | Number of pulses for active energy of cur dem interv (`LSB`)
-| `005` | `0-6` | Number of pulses for active energy of cur dem interv (`MSB`)
-| | `7` | Not used
-| `006` | `0-7` | Number of pulses for reactive energy of cur dem interv (`LSB`)
-| `007` | `0-6` | Number of pulses for reactive energy of cur dem interv (`MSB`)
-| | `7` | Not used
-| `008` | `0-7` | Inverted bits of _xor_ from previous octects
diff --git a/modbus/README.md b/modbus/README.md
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-# Modbus
-
-This directory contains a port of last open source version of FreeModBus (BSD
-license). The code in this directory is a subset of FreeModBus version 1.5.0
-(June 6, 2010) that can be downloaded in its entirety from
-http://developer.berlios.de/project/showfiles.php?group_id=6120.
-
-Includes extensions to support RTU master mode by Armink(383016632@qq.com):
-https://github.com/armink/FreeModbus_Slave-Master-RTT-STM32. Ported to NuttX by
-Darcy Gong.
-
-## Directory Structure / Relation to freemodbus-v1.5.0
-
-The original FreeModBus download consists of several directories. This subset
-takes only the contents of one directory, `modbus/`, that implements the core
-modbus logic and integrates that directory into the NuttX build system. The
-mapping between `freemodbus-v1.5.0` and the nuttx directories is shown below:
-
-```
---------------------------- ----------------------------------------------
-freemodbus-v1.5.0 NuttX
---------------------------- ----------------------------------------------
-All top level .txt files Not included
-demo/ Not included. This directory contains demo
- and porting code for a variety of platforms.
- The NuttX demo was ported from the LINUX
- demo in this directory and can be found at
- apps/examples/modbus.
-doc/ Not included. This directory contains Doxygen
- support files.
-modbus/ Included in its entirety in various locations:
- ascii apps/modbus/ascii
- functions apps/modbus/functions
- include apps/include/modbus
- mb.c apps/modbus/mb.c
- rtu apps/modbus/rtu
- tcp apps/modbus/tcp
-tools/ Not included. This directory contains Doxygen
- tools.
---------------------------- ----------------------------------------------
-```
-
-So this directory is equivalent to the `freemodbus-v1.5.0/modbus` directory
-except that (1) it may include modifications for the integration with NuttX and
-(2) the modbus/include directory was moved to `apps/modbus`.
-
-The original, unmodified `freemodbus-v1.5.0` was checked in as SVN revision
-`4960`.
-
-The other directory here, `nuttx/`, implements the NuttX modbus interface. It
-derives from the `freemodbus-v1.5.0/demo/LINUX/port` directory.
-
-## Configuration Options
-
-In the original `freemodbus-v1.5.0` release, the FreeModBus configuration was
-controlled by the header file `mbconfig.h`. This header file was eliminated
-(post revision `4960`) and the FreeModBus configuration was integrated into the
-NuttX configuration system.
-
-The NuttX-named configuration options that are available include:
-
-- `CONFIG_MODBUS` – General ModBus support.
-- `CONFIG_MB_ASCII_ENABLED` – Modbus ASCII support.
-- `CONFIG_MB_ASCII_MASTER` – Modbus ASCII master support.
-- `CONFIG_MB_RTU_ENABLED` – Modbus RTU support.
-- `CONFIG_MB_RTU_MASTER` – Modbus RTU master support.
-- `CONFIG_MB_TCP_ENABLED` – Modbus TCP support.
-- `CONFIG_MB_ASCII_TIMEOUT_SEC` – Character timeout value for Modbus ASCII. The
- character timeout value is not fixed for Modbus ASCII and is therefore a
- configuration option. It should be set to the maximum expected delay time of
- the network. Default: `1`.
-- `CONFIG_MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS` – Timeout to wait in ASCII prior
- to enabling transmitter. If defined the function calls `vMBPortSerialDelay`
- with the argument `CONFIG_MB_ASCII_TIMEOUT_WAIT_BEFORE_SEND_MS` to allow for a
- delay before the serial transmitter is enabled. This is required because some
- targets are so fast that there is no time between receiving and transmitting
- the frame. If the master is too slow with enabling its receiver then it will
- not receive the response correctly.
-- `CONFIG_MB_FUNC_HANDLERS_MAX` – Maximum number of Modbus functions codes the
- protocol stack should support. The maximum number of supported Modbus
- functions must be greater than the sum of all enabled functions in this file
- and custom function handlers. If set too small, adding more functions will
- fail.
-- `CONFIG_MB_FUNC_OTHER_REP_SLAVEID_BUF` – Number of bytes which should be
- allocated for the Report Slave ID command. This number limits the maximum size
- of the additional segment in the report slave id function. See
- `eMBSetSlaveID()` for more information on how to set this value. It is only
- used if `CONFIG_MB_FUNC_OTHER_REP_SLAVEID_ENABLED` is set to `1`.
-- `CONFIG_MB_FUNC_OTHER_REP_SLAVEID_ENABLED` – If the Report Slave ID function
- should be enabled.
-- `CONFIG_MB_FUNC_READ_INPUT_ENABLED` – If the Read Input Registers function
- should be enabled.
-- `CONFIG_MB_FUNC_READ_HOLDING_ENABLED` – If the Read Holding Registers function
- should be enabled.
-- `CONFIG_MB_FUNC_WRITE_HOLDING_ENABLED` – If the Write Single Register function
- should be enabled.
-- `CONFIG_MB_FUNC_WRITE_MULTIPLE_HOLDING_ENABLED` – If the Write Multiple
- registers function should be enabled.
-- `CONFIG_MB_FUNC_READ_COILS_ENABLED` – If the Read Coils function should be
- enabled.
-- `CONFIG_MB_FUNC_WRITE_COIL_ENABLED` – If the Write Coils function should be
- enabled.
-- `CONFIG_MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED` – If the Write Multiple Coils
- function should be enabled.
-- `CONFIG_MB_FUNC_READ_DISCRETE_INPUTS_ENABLED` – If the Read Discrete Inputs
- function should be enabled.
-- `CONFIG_MB_FUNC_READWRITE_HOLDING_ENABLED` – If the Read/Write Multiple
- Registers function should be enabled.
-
-See also other serial settings, in particular:
-
-- `CONFIG_SERIAL_TERMIOS` – Serial driver supports `termios.h` interfaces
- If this is not defined, then the terminal settings (baud, parity, etc.)
- are not configurable at runtime.
-
-## Note
-
-The developer of FreeModBus, Christian Walter, is still developing Modbus
-libraries, although they are now commercial. See
-http://www.embedded-solutions.at/ for further information.