| Feature | A4 | A6 | A8 | A16 |
|---|---|---|---|---|
| Best Price | £21.80 | "SuperDeal" £17.59 / "Limited Deal" £11.78 | £34.69 | £20.09 / "SuperDeal" £12.86 |
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| Digital Outputs |  |
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| Analog Inputs |   |
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| Analog Outputs |  |
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| Ethernet |  |
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| Wi-Fi |  |
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| Bluetooth |  |
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| RS485 | |
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| RS232 |  |
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| RF433MHz |  |
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| IR |  |
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| I2C | |
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| SPI | |
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| Buzzer |  |
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| RTC | |
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