Re: TTL --> fibre

[wpm@aps.anl.gov (Bill McDowell)]

Ian Smith <I.Smith@roe.ac.uk> asks:

> Does anybody use fibre optics to ship up to 100 TTL signals from an EPICS 
> ioc down to the hardware it controls.  The signals I have to send are 
> stepper motor TTL pulses and read back lots of microswitches.



APS have developed several types of TTL fiber optic transmitter and receiver
boards.


Format:      All boards are standard 6Ux160 single width VME format using only
	     power and ground from the VME backplane. Transmitter and
	     receiver daughter boards are plugged into sockets on
	     boards as needed.

Wavelength:  820nm.
Distance:    Over 2000 feet.
Signal Rate: Up to 125 Megabaud.
Cable:       62.5/125um multimode fiber. 
Connectors:  Fiber-ST, TTL-SMB.

1. FOM100 - 1 TTL input drives 6 Fiber ouputs.
2. FOM101 - 1 TTL input drives 1 Fiber output. 6 channels.
3. FOM102 - 2 TTL inputs to 'or' gate, the output of which drives 1 Fiber
            output. 4 Channels.
4. FOM111 - 1 Fiber input drives 6 Fiber outputs.
5. TIM100 - 1 Fiber input drives 1 TTL 50 ohm output. 6 Channels.
6. TIM101 - 1 5Mhz Fiber input drives 1 TTL 50 ohm output. 4 Channels.
7. FTX100 - Fiber Optic Transmitter daughterboard. 
8. FRX100 - Fiber Optic Receiver daughterboard.

The FRX100 receiver has a pulse width range of 2ns-50us. For slow baud
rates and/or wide pulses (to DC) we use the TIM101 module. The TIM101
does not use plug in fiber receiver daughterboards.