SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
The HDQ1W has two main modes: HDQ and 1-Wire. Each of these modes includes idle, active, and power-down submodes. Table 26-58 lists the HDQ1W functional modes, and Figure 26-29 shows an overview of a typical application.
Functions | Description |
---|---|
HDQ | Benchmarq HDQ protocol |
1-Wire | Dallas Semiconductor 1-Wire protocol |
An external pullup is required, because the two protocols use a return-to-1 mechanism (that is, after any command by any of the connected devices, the line is pulled to a logical high level).
The HDQ1W operates according to a command structure that is programmed into transmit command registers (as described in Section 26.2.5.1.2, HDQ1W Low-level Programming Model).
The 1-Wire mode runs at slower speeds than the capabilities of the mode.
Table 26-59 describes the external signal of the HDQ/1-Wire compliant module.
Signal | I/O(1) | Description | Value at Reset |
---|---|---|---|
hdq_sio | I/O | Serial data input/output. Output is open drain type. | HiZ (pulled to 1 by pullup) |
The path from a module pin to device pad(s) is defined at the device I/O logic level. The control module registers assign the specific function to the device pads. For more information on control module settings, see Pad Configuration Registers in Control Module.