What RS232 baud rate do you use? and why?

[GASPER]

I`ve used a baud rate of 4800 E-7-1 and have had no problems uploading or downloading to the haas ,the machine is old though.
And as far as the machine limits on x y axis, the ones we have are mechanical,we have had them changed due to the wires and conduits becoming hard and brittle due to age and have had no problems since.

[gar]

070630-1650 EST USA

GASPER:

Why have you not tried working at higher baud rates than 4800? How long is your cable? How large are your largest files? How small the smallest?

Old age is not the reason your cables fail, but rather the choice of insulating material by HAAS and that the insulation is probably soaked in coolant for the X-axis. PVC insulation is make flexible by the addition of plasticizers, and the coolant leaches these out of the PVC over time. In some cases in as little as 6 months with hydraulic oil.

.

[GASPER]

I have tried higher baud rates but the machine is ancient and is far more stable at 4800,and you are right about the cables but everything deteriorates with age
the new m/cs run at 19200 and the difference is only a few seconds on download

[gar]

070731-0645 EST USA

GASPER:

The data transfer rate is approxoimately 500 bytes/sec @ 4800 baud, 1000 @ 9600, 2000 @ 19.2 k, 4000 @ 38.4 k, and 12,000 @ 115.2 k.

2 seconds for a 1000 byte file, and 2000 seconds (33 minutes) for a 1 meg file at 4800 baud.
0.1 second for 1000 bytes, and 83 seconds (1.4 minutes) for 1 meg at 115.2 kbaud.

Obviously you are dealing with small files if you are dealing with only a few seconds difference between different baud rates.

On your old HAAS are you using handshaking? How old is the machine? With an appropriate cable length you can get reliable data transfer (zero errors) at HAAS's maximum baud rate.

On a 1993 HAAS with a maximum baud rate of 38.4 kbaud you should probably work reliably at that rate with up to 20 ft of Belden 8723 cable. Of course with either hardware or software handshake active. Your RS232 cable length is roughly inversely proportional to baud rate for a given type cable. There are lower capacitance cables than 8723 and these will allow a longer length at a specific baud rate.

.

[Rocko1]

Gar,
I agree with your basic facts and informative as always.

[DRD]

I am moving data at 115.2 on rs232, around 15 feet of belden shielded cable. I also dnc 8-10meg of data with no bproblem at all on a Dell workstaion to a 08 hass vf3.

[gar]

080425-0802 EST USA

DRD:

What is the Belden wire number, and the capacitance per foot?

.

[rardoin]

115.2K...Because I can! Thanks to Betatronics and Gordon (Shameless Plug

RCA

[KenFoulks]

The following lists baud rates and the respective maximum cable lengths:

9600=100 feet
38400=25 feet
115200=6 feet

So, if you have a 10 foot cable use 38400.