CAN-GXFC

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Overview

This module connects the Apollo GX radio (input/output) and the Matronics FuelCheck (input).

Interfaces

  • USART0, RS232 (RX/TX), GX
  • USART1, RS232 (RX/TX), FC
  • no power

Packets

RX0: GX - Moving Map Output

The format of the moving map data output is as follows. Definitions of the output data is included in Table 6 and Table 9. A sample output message is included in Figure 18.

  • Baud rate: 9600
  • Data bits: 8
  • Stop bits: 1
  • Parity: none
  • Output rate: approx. 1 seconds
  • Message length: variable, approx. 83 to 484 characters

The serial output messages are in the following format.

<STX><id><data><it><id><data><it>...<id><data><it><ETX>
<STX> ASCII start of text character (1 byte, 02h)
<id> item designator (1 byte, from following table)
item data (format listed in following table)
<it> item terminator (1 byte, 0Dh)
<ETX> ASCII end of text character (1 byte, 03h)
Table 6 Moving Map ASCII Navigation Data
ID Data Format Length Description
A sddmmhh 9 Present latitude
  • s = sign: N for north, S for south
  • dd = degrees
  • mm = minutes
  • hh = hundredths of minutes
B sdddmmhh 10 Present longitude
  • s = sign: E for east, W for west
  • ddd = degrees
  • mm = minutes
  • hh = hundredths of minutes
C ddd 3 Track (magnetic): ddd = degrees
D ddd 3 Ground speed: ddd = knots
E ddddd 5 Distance to active waypoint: ddddd = nm x 10
G sdddd 5 Cross track error:
  • s = sign: R for right, L for left of course
  • dddd = distance off course, hundredths of nm
I dddd 4 Desired track (magnetic):
  • dddd = degrees x 10
K ddd[dd] 3 to 5 Active waypoint identifier:
  • ddd[dd] = ASCII waypoint identifier
L dddd 4 Bearing to active waypoint (magnetic):
  • dddd = degrees x 10
Q sddd 4 Magnetic variation:
  • s = sign: E for east, W for west
  • ddd = degrees x 10
T ---A----- 9 Warnings: The 4th character will be an A

when the navigation data is flagged, otherwise, all characters will be dashed. All other navigation data will be dashed when it is flagged.

TX0: GX - Fuel/Air Data Computer Input

The fuel / air data input is used to input fuel flow and airdata computer information from the Shadin ADC-200 fuel / air data computer.

The format of the fuel / air data computer input is as follows, which conforms to the Shadin S format serial message. Definition of the input message data that the GX50/60/65 uses is included in Table 12. A sample input message is illustrated in Figure 21.

  • Baud rate: 9600
  • Data bits: 8
  • Stop bits: 1
  • Parity: none
  • Expected input rate: approx. 1 second
  • Message length: variable (512 character max.)

The serial input message string is expected in the following format.

<STX><message><message> ... <message><chksum><ETX>
<STX> ASCII start of text character (STX = 02h)
<message> starts with an ASCII S, then an ID character, followed by the message data, a carriage return (CR = 0Dh), and a line feed (LF = 0Ah) See the following table.
<checksum> the message checksum, same format as message
<ETX> ASCII end of text character (ETX = 03h)
Table 12 Fuel / Airdata Message Data
Item
ID
 Message
Format
 Message
Mnemonic
 Field
Width
 Message Description
SA ddd IAS 7  Indicate Air Speed in knots
SB ddd TAS 7  True Air Speed in knots
SC ddd MACH 7  Mach Speed in thousandths
SD sdddd PALT 9  Pressure Altitude in tens of feet, +/- sea level
SE sdddd DALT 9  Density Altitude in tens of feet, +/- sea level
SF sdd OAT 7   Outside Air Temp - or ìTotalî, in degrees Celsius
SG sdd TAT 7  True Air Temp - or ìStaticî, in degrees Celsius
SH ddd WDIR 7  Wind Direction, 0 to 359 degrees from true north
SI ddd WSPD 7  Wind Speed in knots
SJ sdd TURN 7  Rate of Turn in +/- degrees/second, + is right, - is left
SK sddd VSPD 8  Vertical speed in tens of feet/minute
SL ddd HEAD 7  Heading, 0 to 359 degrees from true north
SM dddd RFF 8  Right Engine Fuel Flow in tenths of gallons/hour
SN ddddd RFU 9  Right Engine Fuel Used in tenths of gallons
SO dddd LFF 8  Left Engine Fuel Flow in tenths of gallons/hour
SP ddddd LFU 9  Left Engine Fuel Used in tenths of gallons
SQ ddd ERR 7  Error Log / Reason Indicator:
  • 001 = temp sensor error;
  • 000 = no errors
S* ddd CKSUM 7 Checksum of all characters preceding this record. The checksum is a one byte checksum (discarding carries) including all characters from the initial STX up to and including the line feed preceding the checksum message.

RX1: FC - The Matronics computer format

         1         2         3         4         5         6         7         8
12345678901234567890123456789012345678901234567890123456789012345678901234567890
?G P S 0008.0 0012.8 0019.5 02:26 015.39 0016.00 012.5 100.0 0366 ------ 013?
                            --:--                ---.- ---.- ----
  • 1 STX (02 Hex)
  • 2 Fuel Units:
G = US Gallons
L = Liters(*)
I = Imperial Gallons
B = Pounds
K = Kilograms
  • 3 Space
  • 4 Pressure Units:
P = Pounds Per Square Inch (PSI)
A = Atmospheres
K = Kilopascals
B = Bars(*)
G = Grams per Centimeter
  • 5 Space
  • 6 Distance Units:
S = Statute Miles
N = Nautical Miles
K = Kilometers(*)
  • 7 Space
  • 8-13 Current Flow Rate Per Hour (ASCII Coded Decimal, MSB first)
  • 14 Space
  • 15-20 Total Fuel Used (ASCII Coded Decimal, MSB first)
  • 21 Space
  • 22-27 Total Fuel Remaining (ASCII Coded Decimal, MSB first)
  • 28 Space
  • 29-33 Total Hours Remaining (ASCII Coded Decimal, MSB first)
  • 34 Space
  • 35-40 Current Cost Per Hour (ASCII Coded Decimal, MSB first)
  • 41 Space
  • 42-48 Fuel Pressure (ASCII Coded Decimal, MSB first)
  • 49 Space
  • 50-54 Current Economy (ASCII Coded Decimal, MSB first)
  • 55 Space
  • 56-60 Ground Speed (Loran/GPS) (ASCII Coded Decimal, MSB first)
  • 61 Space
  • 62-65 Distance to Destination (Loran/GPS) (ASCII Coded Decimal, MSB first)
  • 66 Space
  • 67 Low Fuel Warning Active ( "L" when Active )
  • 68 Low Hours (Time) Warning Active ( "T" when Active )
  • 69 Change (Switch) Tank Warning Active ( "S" when Active )
  • 70 Insufficient Fuel to Destination Warning Active ( "R" when Active )
  • 71 Low Pressure Warning Active ( "p" when Active )
  • 72 High Pressure Warning Active ( "P" when Active )
  • 73 Space
  • 74-76 Packet Checksum (8 bit binary sum of bytes 2 through 73 converted to 3 digit ASCII Coded Decimal, MSB first)
  • 77 ETX (03 Hex)

TX1: FC

Not used