Repeater Mil-Std-1553B Datasheet 1
Summary 1. Environment specification...3 2. Electronic diagram...5 3. Output...6 4. Electrical specifications...7 3. Test...8 3.1. Bus Monitor...8 3.2 Bus Controller...11 3.3 Two repeater...17 2
1. Environment specification Field Requirements Temperature Operational: Start-up: Storage: -15 C / +55 C -40 C / +70 C -55 C / +85 C Decompression Min: - 15,000 ft Max: + 50,000 ft Pressure Drop: ± 12,000 ft/min Humidity 95% humidity @ +50 C Acceleration/Shocks Acceleration: Cat. D, soit 6g pdt 20ms, suivant 3 axes Crash : Cat. E, soit 20g / 20ms (3 axes) Vibrations See next page Explosion Shall not explode EMC Magnetic field < 14.4 A/m @ 3 m Power Supply 28 VDC Micro-cuts 250ms Over voltages 600V on 2µs RF Susceptibility Conducted (10 khz-400 MHz): Cat. R Radiated (100 MHz-8 GHz): Cat. R RF Emitting Conducted: Cat. L/M Radiated: Cat. M Lightning induced Susceptibility On internal buses The system shall meet the following curve ( Within one propeller radius of propeller plane from MIL-STD 810F, 514.5): 3
APSD g²/hz 1 0.1 0.01 0.001 10 100 1000 Frequency Hz Location One propeller radius w.r.t the propeller plane Broadband F0 2F0 3F0 4F0 background 78Hz 118Hz 159Hz 236Hz 239Hz 354Hz 369Hz 472Hz 0.005 g²/hz 0.6 0.15 0.066 0.0375 4
2. Electronic diagram 5
3. Output Triax connectors on front panel are from left to right: Bus 1A, 1B, 2A, 2B. The LED's associated with each connector are LH LED = Rx, RH LED = Tx. A signal IN on Bus 1A will be OUT on Bus 2A and the appropriate LED's will indicate Rx and Tx respectively. Similarly a signal IN on Bus 2B will be OUT on Bus 1B again with the appropriate LED's illuminated. 6
4. Electrical specifications 28V Power Connector provided on back panel. Mating connector supplied without leads. Customer to provide correct length and type of cable. Power connection Pin 1 +28V Pin 2 GND (Chassis) Pin 3 0V Looking at the rear of the repeater as in this image: Pin 1 of the Power connector is on the Right Pin 2 of the Power connector is Upper Centre. Pin 3 of the Power Connector is on the Left. 7
3. Test 3.1. Bus Monitor The repeater (only one channel) is used to link a 1553 bus with real devices to a remote monitor. A real dialog between BC and RTs is done on the "working bus". This test was completely run four time without raising any error. Such a test was previously working with ATT repeater first version, but was not working with another repeater. Oscilloscope 1553 stub coupler 1553 termination > 20 m MONITORING BUS 1553 RT Repeater 1553 RT WORKING BUS 1553 monitor 1553 BC Following oscillograms (D032, D034 et D033) show the 1553 signal at the two repeater ends. Trace #2 (down) : signal on the working bus (stub) Trace #1 (up): signal on the monitoring bus (main bus) (The trace #2 signal seems inverted because the differential probe connections were inverted.) 8
D032.BMP 9
D034.BMP 10
D033.BMP 3.2 Bus Controller The repeater (only one channel) is used to link a 1553 bus with real RT devices to a remote BC. Using an appropriate subaddress, BC is first writing some data in one of the RT, the data are then read back from the RT memory, using another subaddress, and compared to the initial data. This test was run twice : with 1 data word transfers (data value being incremented at each cycle) and with 32 random data words transfers. Results : - With one data word : > 70000 cycles without any error - With 32 data words : > 61000 cycles without any error Such a test was not working with ATT repeater first version. 11
Oscilloscope 1553 stub coupler 1553 termination > 20 m BC BUS 1553 RT Repeater Not used RT BUS BC Not used Following oscillograms (D025, D028, D030 et D031) show the 1553 signal at the two ends of repeater. Trace #1 (up): signal on the BC bus (main bus) Trace #2 (down) : signal on the RT bus (stub) (The trace #2 signal seems inverted because the differential probe connections were inverted.) 12
D025.BMP 13
D028.BMP 14
D030.BMP 15
D031.BMP Preceding oscillograms show some noise on the BC bus ( 300 khz sinus) (probably a bad 1553 wire, but still to be confirmed). Nevertheless, this noise didn't induce any transmission error. The two last oscillograms (D030 et D031) display the end of a status word returned by a RT. The second one (D031) shows an extra bit at the end of the status word. This extra bit, which is roughtly shown every ten cycles, doesn't seem harmful to the 1553 data transfers. 16
3.3 Two repeater The two ATT repeater channels are linked together with two 60 m 1553 main bus. Host 1553 I/F 1553 I/F Terminatio n Length 60 m 2B 1A Stub couplers 1B ATT Repeater 2A Length 60 m The host computer is simultaneously managing a BC and a RT I/F. Transmission and reception 1553 transfers, with random data words, are repeatedly emitted. Received data are compared to transmitted data. With 1 data word transfers : 3.5E6 messages ( 1E7 words) were sent without any error. With 32 data word transfers : 3.0E6 messages ( 1E8 words) were sent without any error. No error was seen. 17