Serial port questions

[happy Profile]

I assume, that your TTL/RS232 converter cable is passive. It tries to steal power from the WiSnap, usually from the pins DTR, DSR or DCD, which are not connected by default.
It is like with the cables described here:
http://casiopeia.net/forum/viewtopic.ph ... rial+3+pin

Since I followed the link Helder gave there (http://www.pfranc.com/pclink/myidea.htm) and from there to the 'For Sale' page for FA-122, I am sure you are right!

Does your TTL/RS232 converter have means to connect its own external power supply?
Does the manual of your TTL/RS232 converter say, which line of the external RS232-device is used to steal power?

There is no manual..

Try to contact the WiSnap manufacturer and ask, if it could be a problem to set one of the jumpers to drive DTR, DSR or DCD. Perhaps it is sufficient to drive one of the WiSnap pins DTR, DSR or DCD.

Will do.

I use active TTL/RS232-converters

Where can I buy one..?

Sorry, I should have thought of it earlier.

I am very grateful you are working with me through this!

[SimonLothar]

I use active TTL/RS232-converters

Where can I buy one..?

I build them myself. I take the power from USB ports.

It would be not this difficult to construct an adapter, which could be positioned between WiSnap and the converter cable. It would take its power from some USB port, f. i..

EDIT: But this would only be necessary, if the WiSnap cannot supply sufficient power.

[happy Profile]

I build them myself. I take the power from USB ports.

It would be not this difficult to construct an adapter, which could be positioned between WiSnap and the converter cable. It would take its power from some USB port, f. i..

EDIT: But this would only be necessary, if the WiSnap cannot supply sufficient power.

Waiting for them to respond.. Meanwhile could you kindly post a pic of your cable?

[happy Profile]

They replied, "what DB9 pin does the FA-122 cable get power from?". How do I find out?

[SimonLothar]

They replied, "what DB9 pin does the FA-122 cable get power from?". How do I find out?

According to the CASIO FA-122 link cable picture helder7 posted here

http://www.casiopeia.net/forum/viewtopi ... =20&t=1473

it is pin 4 (9-pin D female; white), which -according to page 8 (2.6.3) of the WiSnap manual- is DTR with the WiSnap male connector.

[SimonLothar]

Meanwhile could you kindly post a pic of your cable?

Basically it is like Alternative Cable (1) (http://www.casiopeia.net/forum/viewtopi ... =20&t=1473).
But I do not use the DB9 pins 4, 6, 7, 8 as power supply. Hence I do not need the diodes 1N4148, the voltage regulator 78L05 and the 9V supply.
Instead I power the MAX232 (pin 16) directly with the 5 V line of some USB port. The USB GND connected to the converter GND (f. i. MAX232 pin 15), of course.

[SimonLothar]

They replied, "what DB9 pin does the FA-122 cable get power from?". How do I find out?

According to the CASIO FA-122 link cable picture helder7 posted here

http://www.casiopeia.net/forum/viewtopi ... =20&t=1473

it is pin 4 (9-pin D female; white), which -according to page 8 (2.6.3) of the WiSnap manual- is DTR with the WiSnap male connector.

As the FA-122 picture shows a resistor between RTS(7) and RxD(2), I read the FA-122-converter's patent full text (http://www.pfranc.com/pclink/myidea.htm -> "My patent"). It says "...DTR (+V)...RTS(-V)...".
That means the RTS is needed, too, as negative power supply. Hence the FA-122 needs a bipolar power supply (3..15V, symmetrical; typical 8-10V). If the connected device (normally a PC) does not support this, FA-122 cannot work as it is. T. i. some power supply adapter (f. i. MAX681-based) between FA-122 and connected device or a MAX232/233-based cable is needed.
According to page 30 of the WiSnap, RTS goes low after the system is ready. So if low is meant to be -V, the requirements seem to be fulfilled with the WiSnap. But better have the manufacturer confirm this.

[Arkhs Profile]

Is possible to receive and send data (with WiSnap and fx9860) or just send?

[happy Profile]

Is possible to receive and send data (with WiSnap and fx9860) or just send?

Only send, AFAIK.

According to page 30 of the WiSnap, RTS goes low after the system is ready. So if low is meant to be -V, the requirements seem to be fulfilled with the WiSnap. But better have the manufacturer confirm this.

Sorry, was away from my computer last 3 days. I have asked, let's see if they repond. Problem is they charge for support by the hour.

As of now, the mail trail between the support team and me is as follows:
Support: what DB9 pin does the FA-122 cable get power from?

Me: It is pin 4 (9-pin D female; white), which - according to page 8 (2.6.3) of the WiSnap manual - is DTR with the WiSnap male connector.

Support: use multimeter to find 3.3V power when the unit is powered up on batteries
then solder a wire from pin4, to that point.

Does this help?

[SimonLothar]

Support: use multimeter to find 3.3V power when the unit is powered up on batteries
then solder a wire from pin4, to that point.
Does this help?

I don't think so. Though the RS232-level-specification is 3..15 V, I think 3.3 V is too near to the lower limit. The risk of a communication failure is too high. Above that, the RTS problem is not solved, yet.
And if you have to solder anyhow, you'd rather build an active adapter for your FA-122, based on a MAX681.