Polycom C8, SR12, C12, C16 manual Logic Inputs

Installing The SoundStructure C16, C12, C8, And SR12

8	Logic Output 18	21	Logic Input 19
9	Logic Output 19	22	Logic Input 20
10	Logic Output 20	23	Logic Input 21
11	Logic Output 21	24	Logic Input 22
12	Logic Output 22	25	Ground
13	Analog Gain 2

Logic Inputs

All digital logic inputs (logic inputs 1 - 22) operate as contact closures and may either be connected to ground (closed) or not connected to ground (open). The logic input circuitry is shown in the following figure. Chapter 4 Logic Examples provides examples of how to use the logic input pins.

SoundStructure Logic Input

3.3V

Logic

Status

Logic Input Pin

Logic Pin 25 (Ground)

Analog Gain Input

The analog gain inputs (analog gain 1 and 2) operate by measuring an analog voltage between the analog input pin and the ground pin. The maximum input voltage level should not exceed +6 V. It is recommended that the +5 V supply on Pin 1 be used as the upper voltage limit.

The following figure shows the analog gain input pin and the associated +5 V and ground pins that are used with the analog gain input pin. The analog voltage on the analog gain input pin is converted to a digital value via an 8-bit analog-to-digital converter for use within the SoundStructure devices. The maximum voltage value, i.e., 0 dBFS on the analog gain input, is 4.096 V. The SoundStructure API commands analog_gpio_min and analog_pio_max are used to map the values into a desired range of numerical values. By default 0 V is converted to 0 and 4.096 V and above is converted to 255.

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