The PCF8574 I/O Expander is an I²C device in the LabWired part catalog. Its catalog type is pcf8574. It connects to the MCU over I²C at the default address 0x20. The catalog gives a supply range of 2.5–6 V. It has 13 pins. A registered peripheral model runs in the engine: the firmware talks to it over the real bus and gets device-accurate responses.
From the catalog: I²C quasi-bidirectional I/O expander; port levels host-readable, not a full GPIO fabric.
| Category | I²C devices |
|---|---|
| Catalog type | pcf8574 |
| Interface | I²C |
| Default I²C address | 0x20 (32 decimal) |
| Supply range | 2.5–6 V |
| Pins | 13 |
| Datasheet | Texas Instruments PCF8574 datasheet |
Simulated device model
Built from the datasheet. Implemented from the part’s register documentation and exercised by automated tests. Nothing physical was ever placed next to it.
| Pin | Electrical type | Function |
|---|---|---|
VCC | Power input | Supply |
GND | Power input | Supply |
SDA | Open-drain | I²C data (SDA) |
SCL | Open-drain | I²C clock (SCL) |
INT | Output | — |
P0 | Passive | — |
P1 | Passive | — |
P2 | Passive | — |
P3 | Passive | — |
P4 | Passive | — |
P5 | Passive | — |
P6 | Passive | — |
P7 | Passive | — |
Modelled from Texas Instruments PCF8574 datasheet.