Shure P4800 - 4;-10 Scaling; Volume Control

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+4/-10 scaling
Toggle
Input 1: F0h 00h 01h 00h <Device ID> 0Ah 69h 06h 00h 0Ch 00h F7h
Input 2: F0h 00h 01h 00h <Device ID> 0Ah 69h 06h 00h 0Dh 00h F7h
Input 3: F0h 00h 01h 00h <Device ID> 0Ah 69h 06h 00h 0Eh 00h F7h
Input 4: F0h 00h 01h 00h <Device ID> 0Ah 69h 06h 00h 0Fh 00h F7h
Force +4 dBu scaling
Input 1: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Ch 00h F7h
Input 2: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Dh 00h F7h
Input 3: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Eh 00h F7h
Input 4: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Fh 00h F7h
Force –10 dBV scaling
Input 1: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Ch 7Fh F7h
Input 2: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Dh 7Fh F7h
Input 3: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Eh 7Fh F7h
Input 4: F0h 00h 01h 00h <Device ID> 0Ah 69h 01h 00h 0Fh 7Fh F7h
Volume control
Set volume to a specific value
Input 1: F0h 00h 01h 00h <Device ID> 0Ah 69h 00h 00h 00h <VA> F7h
Input 2: F0h 00h 01h 00h <Device ID> 0Ah 69h 00h 00h 01h <VA> F7h
Input 3: F0h 00h 01h 00h <Device ID> 0Ah 69h 00h 00h 02h <VA> F7h
Input 4: F0h 00h 01h 00h <Device ID> 0Ah 69h 00h 00h 03h <VA> F7h
where, <VA> = [ 2 * (Control Setting) ] & 7Fh
i.e., multiply the control setting by 2 and then logically AND that product with 7Fh.
The valid range for “Control Setting” is (-30) to (30). Each integer increase (or decrease) in the Control Setting is
equal to 1 dB change.
Increase/Decrease volume by a relative amount
Input 1: F0h 00h 01h 00h <Device ID> 0Ah 69h 04h 00h 00h <VA> F7h
Input 2: F0h 00h 01h 00h <Device ID> 0Ah 69h 04h 00h 01h <VA> F7h
Input 3: F0h 00h 01h 00h <Device ID> 0Ah 69h 04h 00h 02h <VA> F7h
Input 4: F0h 00h 01h 00h <Device ID> 0Ah 69h 04h 00h 03h <VA> F7h
where, <VA> = [2 * (dB Change) ] & 7Fh
i.e., multiply the amount of change (in dB) by 2 and then logically AND that product with 7Fh. For
example, to decrease the volume by 2 dB:
<VA> = [2 * (-2)] & 7Fh
<VA> = [-4] & 7Fh
<VA> = 7Ch
It is not necessary to calculate this equation by hand. Both AMX and Crestron can be programmed to calculate
this equation.