Apollo GX50, Руководство по установке

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Serial Interface Specifications
Apollo GX50/60/65 Installation Manual
61
A
LTITUDE
E
NCODER
/C
ONVERTER
I
NPUT
The format of the altitude input is as follows. Definition of the input message is included in
Table 11. Several sample messages are illustrated in Figure 20.
Baud rate: .......................................... 1200
Data bits: ........................................... 8
Stop bits: ........................................... 1
Parity: ............................................... none
Expected input rate: .......................... approx. 1 second
Message length: ................................ 17 characters
Table 11 Altitude Input Data
Byte Data Format Description
1 “#” ASCII “#” (023h)
2 “A” ASCII “A” (041h)
3 “L” ASCII “L” (04Ch)
4 “ “ ASCII space (020h)
5 “+” or “-” Altitude sign: ASCII “+” or “-” (02Bh or 02Dh)
6-10 ddddd Altitude in feet, right justified with leading zeros
11 “T” ASCII “T” (054h)
12 “+” or “-” Temperature sign: ASCII “+” or “-” (02Bh or 02Dh)
13-14 dd Internal altimeter temperature
15-16 dd Checksum of bytes 1 through 14, computed in hex, output in
ASCII format (i.e., “FA” hex)
17 <CR> ASCII carriage return (0Dh)
The altitude input can decode several status or error codes. These codes would be in place of
the altitude data in characters 5 - 10 as follows.
“-09980” ............................................ Heater not ready: expected during encoder warm-up
or if there is a loss of signal from the encoder.
“-09981” ............................................ Possible hardware problem: expected from encoder
indicating a temperature greater than 55
°
C or if data
is invalid.
“-09982” ............................................ Altitude out of range: expected from the encoder
indicating that the altitude is outside specified range
of the encoder.