Classes | |
class | Device |
class | Request |
struct | StateMask |
Tracks state of multiple relays. More... | |
Variables | |
constexpr uint8_t | R421_CHANNEL_MIN = 1 |
constexpr uint8_t | R421A_MAX_CHANNELS = 16 |
Detailed Description
Created on: 1 May 2018
Copyright 2022 mikee47 mike@ sill yhous e.ne t
This file is part of the IOControl Library
This library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 or later.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this library. If not, see https://www.gnu.org/licenses/.
R421A08 modbus 8-channel relay board
Channels are numbered 1 - 8. This is the 16-bit address field in a request.
To simplify operation we use a bitmask to specify relay states. We use the channel number directly so values can range between 0x0001 and 0x01FE
The query command returns a range of states, but other commands work with only a single channel. We therefore implement a mechanism to iterate through all requested channels using the same request.
There is a similar 4-channel board but with no markings and (as yet) no documentation. However all commands appear to work so a designation of R421A04 seems appropriate. Some typos in the 8-channel datasheet indicate that it was adapted from that of a 4-channel version.
R421A04 - 32 addresses set with DIP1-5, DIP6 ON for RTU mode R421A08 - 64 addresses set with DIP1-6, RTU mode only
Created on: 1 May 2018
Copyright 2022 mikee47 mike@ sill yhous e.ne t
This file is part of the IOControl Library
This library is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 or later.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this library. If not, see https://www.gnu.org/licenses/.
Variable Documentation
◆ R421_CHANNEL_MIN
|
constexpr |
◆ R421A_MAX_CHANNELS
|
constexpr |