UPS Aviation Technologies Apollo SL70R, Installation Manual

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Serial Interface Specification
Apollo SL70R Installation Manual
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Both the encoder and converter will send this code when the altitude is outside the speci-
fied limits for the device.
7.3.2
M
ODE
M
ESSAGE
The mode message indicates the current operating mode. It includes the following: 1)
current mode, Standby, Mode A or Mode C, 2) Ident enabled/disabled, 3) current
Squawk code setting and 4) heart beat received. This message is output in both normal
and test modes.
7.3.2.1 I
NTERFACE
S
PECIFICATION
Output Rate: Approx. 1 sec. when EXT (extended) messages are selected.
Buffer Length 17 bytes
7.3.2.2 M
ODE
F
ORMAT
S
PECIFICATION
Table 7-3. Mode Message Format
Byte Contents Description
0
‘^’ ASCII ‘^’ (0x5E)
1 ‘M’ ASCII ‘M’ (0x4D)
2 ‘D’ ASCII ‘D’ (0x44)
3 ‘ ‘ ASCII space (0x20)
4 m See Mode Table below
5 ‘, ‘ ASCII comma (0x2C)
6 i See Ident Table Below
7 ‘,‘ ASCII comma (0x2C)
8-11 dddd ASCII Squawk code
12-13 hh LSB = 1 heart beat received In hex ASCII “01”
14-15 dd Checksum of bytes 0 through 13. In hex ASCII i.e. “FA”
16 ‘\r’ ASCII carriage return (0x0D)
Table 7-4. Mode Table
m Definition ASCII
O Standby Mode 0x4F
A Mode A 0x41
C Mode C 0x43
Table 7-5. Ident Table
i Definition ASCII
I Ident Enabled 0x49
- Ident is Inactive 0x2D
7.3.2.3 M
ODE
M
ESSAGE
E
XAMPLES
^MD O,-,12000006 Standby Mode, Ident inactive, Squawk code is 1200
^MD A,I,23540120 Mode A, Ident active, Squawk code is 2354