Reading Mil Std 1553B output

Buy a 1553 interface card?

Can I connect the port to the rx pin of the 9 pin serial port and make any sense? Are the 1553B interface cards standard or does it have to be custom made depending on the equipment

That's a start...

MIL-STD-1553 is a balanced signal (has a + wire, a - wire and a ground/shield) for each channel. One channel usually has DUAL REDUNDANCY, meaning Channel 1A and channel 1B... if channel 1A fails (and the box is programmed correctly), channel 1B will be used (why? because it isn't nice flying home with half an airplane).

The signal strength comes in two "volumes": DIRECT COUPLED and TRANSFORMER COUPLED. Direct is 3V to 9V p-p. Transformer is 9v - 27v p-p. When reading these signals, clip an O-scope Channel A onto 1553 Channel 1A+ and O-scope Channel B onto 1553 Channel 1A-. select ADD and INVERT on your O-scope.

MIL-STD-1553 is a 20-bit stream.

Bits 0, 1, 2 are SYNC. Bits 3, 4, 5, 6, 7 are Remote Terminal Bit 8 is Transmit/Receive Bits 9, 10, 11, 12, 13 are Subaddress Bits 15,16,17, 18, 19 are Word Count/Mode Code Bit 20 is Parity

The 1553 language is standard world-wide (yes, the same stuff from Bejing to Hoboken). How you get it to talk, or fill data buffers, or address Remote Terminals and Subaddresses with Mode Codes or Data is proprietary, so you will have to surf the site of the manufacturer.

Have fun!

Excalibur make 1553 interface cards but they are about £1500 each. The data (as I recall, no doubt someone will correct/clarify...) is a serial differential transformer coupled stream, at 1Megbaud. Each data word is 16 bits, with a couple of start and stop bits. The words are grouped in messages, and sent under control of the bus controller. You may have a controller or remote terminal (slave device). The voltage level ranges from 3 to 30 volts. Probably difficult to get a com port to talk/listen. hope this helps, Neil

The MIL-STD-1553B "output" from the board can range from 3vdc to 27vdc. You do not want 27vdc on your computer's comm port.

However, there is a TRANSCEIVER on the board somewhere. This transceiver has one side digital TTL levels (toward the circuitry) and one side analog (3vdc/9vdc or 9vdc/27vdc - toward the output).

The transceiver IC usually has a brass tint to it, with twenty legs. The number on top will give you something to Google. Some of the TTL legs are TXA+, TXA-, TXB+, TXB-.

Before clipping on to these TTL legs, please make sure your COMM port can handle the voltage levels... please?

There might be another odd-looking connector, that would be the Discrete Output Signal port. It operates in RS-422 (balanced) and can be used as an input or output for synchronizing devices in the system.

Just a little more info on 1553:

- It is a command/response system.

- The Bus Controller does all the commanding

- The Remote Terminal(s) do all the responding.

- Remote Terminals can range from 0 to 31 (five bits)

- Each Remote Terminal can have up to 32 Subaddresses (five bits, 0 to 31)

- The bus architechture is like that of the old-school thicknet ethernet.

- A 1553 device will have a "stub" that connects the device to a "T" or "Transformer Coupler"

- The "T" or "Transformer Coupler" connect the stub to the bus (backbone).

- Each end of the bus is terminated, to reduce reflected waves below the

Guess that's all for now. Time for dinner.

Neil C.? GE32?

I'm Neil from Chatham in Kent, England. Work (currently) for BAE Systems. Not sure what the GE32 is, so it's probably not me you're thinking of.

BAE - GoldExpress, perhaps.

Try this 1553 introduction: