AVM AVM RS232, Руководство пользователя

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AVM RS232 Programming — Crosspoint Messages (Class 2)
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AVM RS232 Programming — Crosspoint Messages (Class 2)
Conversions of ramp times and slew rates
Convert from a known decimal value to a hex transmission value:
To convert a desired decimal value (N) to a 2-byte value to transmit to the matrix mixer:
1) N ÷ 256
2) The integer part of the result from step 1 is the most significant byte of the 2-byte result.
3) The remainder from step 1 is the least significant byte.
4) Convert the two bytes to hexidecimal.
5) The most significant byte is transmitted first.
Example1:
You wish to transmit the slew rate 7:
7 ÷ 256 = 0 with a remainder of 7. The two hexidecimal bytes to transmit are 00h and 07h.
Example 2: You wish to transmit the ramp time 20,000:
20,000 ÷ 256 = 78 with a remainder of 32. Converting 78 and 32 to dexidecimal gives: 4Eh and
20h.
Convert from a two byte transmission value to a decimal value:
1) Convert the most significant byte from hex to decimal and multiply by 256.
2) Convert the least significant byte from hex to decimal and add it to the result of step 1.
Example 1:
You receive the two hex bytes 00h and 09h:
00 * 256 = 0. 0 + 9 = 9. The value represented is 9.
Example 2: You receive the bytes 41h and 21h:
41h => 65d; 65 *256 = 16640.
21h => 33d; 16640 +33 = 16673. The transmitted value was 16673.
Ramp times and slew rates are transmitted to and from the matrix mixer as a pair of
hexidecimal bytes. The following section shows how to convert to and from
transmission values and decimal numbers.
The pair of bytes is always transmitted and received most significant byte first.