Re: [CAD_CAM_EDM_DRO] Hp 7475 Plotter Servo's

Hi Alan,

I may be completely wrong as this is from memory of some 15+ years ago. I
bought my 7475 and it came with a 5 1/4" disk of software. I was using Win
3.1 at the time and for one reason or another couldn't get the thing going
from this operating system. The shop I bought it from had gone out of
business and so twelve months later took the 7475 to Rapid Computors, here
in Liverpool. They charged me £50 ($75) to tell me they couldn't get it
going and it must be broken.

On talking to a friend it was suggested I use the software and read the
instructions again and the thing worked. It seems the software sets up a
"scratch disk" on the hard drive, it reserves an area of hard disk for its
exclusive use, similar to what Windoz O/S does. This "scratch disk" is not
necessary when using Win95 of later as they have drivers built in.

I also seem to remember in the instructions there was a DOS routine that
could be typed to test the connection, I used it when I made up a longer
cable. I also remember there is something odd about the RS232 cable wiring.

Regards,

Terry


| Hi Terry,
|
| "scratch disk software"? What would that be?
|
| The HP7470 and HP7475A plotters (and probably ALL of the serial HP
plotters)
| respond to simple ASCII command strings. It looks like this:
|
| .@1024;3: IN PS0 PA0,0 IW458,618 16639,10364 VS127 PR9607,9847 SP1 PD
| PR0,-8680 PU 0,8680 PD 291,-102 PU -3765,-302 PD 0,-495 PU 3218,774 PD
0,-495
| PU -3218,216 PD 3218,279 PU -3218,-774 PD 3218,279 PU -3157,155 PD 0,-373
|
| To send a .plt file to the plotter in DOS, one only has to initialize the
comm
| port, and "copy" the file to the appropriate COM port.
|
| In windowz, you'll need a driver for the plotter. I believe HP7475 is one
of
| the defaults supplied in Windoz98.
|
| Alan KM6VV
|
| Blue wrote:
| > Hi,
| >
| > I also have a 7475 I haven't used in a while. as far as I recall it
won't
| > work in DOS without the scratch disk software and in Windoz it does. It
| > requires a standard cable if a remember right but there is a site that
deals
| > with this if you search via google.
| >
| > Regards,
| >
| > Terry