Table 7−1. GPI Terminal Programming
| GPI5 | GPI4 | GPI3 | GPI2 | GPI1 | GPI0 |
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VOL_UP, +1 dB | x |
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VOL_DN, −1 dB |
| x |
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BASS_UP, +1 dB |
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| x |
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BASS_DN, −1 dB |
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| x |
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TREB_UP, +1 dB |
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| x |
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TREB_DN, −1 dB |
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| x |
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Shift 1 | x |
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| x |
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Mute | x |
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EQ1 |
| x |
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EQ2 |
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| x |
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EQ3 |
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| x |
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EQ4 |
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| x |
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EQ5 |
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| x |
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Shift 2 |
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| x | x |
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NOTE: x = Logic low |
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Initially (after reset), the TAS3002 GPI is set to control volume, bass, and treble. Simultaneously setting GPI bits 1 and 5 low for 1 second changes the function of the GPI terminals to control mute and equalization.
To return to volume, bass, and treble control, simultaneously set GPI terminals 2 and 3 low for 1 second.
When a GPI terminal is activated, the TAS3002 device echoes its function over I2C to a TAS3001 device mapped to address 6Ah. Therefore, a system with two audio equalization chips can be implemented without the need for a microcontroller.
7.6.2GPI Architecture
The GPI provides simple but flexible input port to activate the input parameters. Each terminal input is an active logic low.
7−5