mat@emcard.UUCP (W Mat Waites) (01/09/91)
I'm trying to print bitmaps files to a Laserjet via LPT1: and the image
gets all trashed. I'm wondering if LPT1: is only passing 7 bits, playing
with what it thinks are tabs, etc. I know the file is good because I can
print it to a Laserjet from a Unix system (serial interface) and it works
fine.
How can I get raw data through the parallel port?
Thanks,
Mat
--
W Mat Waites | Walking the wire is living,
{gatech,emory}!emcard!mat | the rest is just waiting. - Wallendafrank@cavebbs.gen.nz (Frank van der Hulst) (01/10/91)
In article <8280@emcard.UUCP> mat@emcard.UUCP (W Mat Waites) writes: > >I'm trying to print bitmaps files to a Laserjet via LPT1: and the image >gets all trashed. I'm wondering if LPT1: is only passing 7 bits, playing >with what it thinks are tabs, etc. I know the file is good because I can How are you doing it -- if you want to do it from DOS, try COPY/B FILE LPT1: -- the /B tells DOS it's binary, and not to stop at a ^Z. The same type of problem applies to TurboC/Pascal -- it thinks the printer is a text device, so it bombs out on ^Zs... there are workarounds, although I don't know the specifics of them. -- Take a walk on the wild side, and I don't mean the Milford Track.
stanley@phoenix.com (John Stanley) (01/10/91)
frank@cavebbs.gen.nz (Frank van der Hulst) writes: > In article <8280@emcard.UUCP> mat@emcard.UUCP (W Mat Waites) writes: > > > >I'm trying to print bitmaps files to a Laserjet via LPT1: and the image > >gets all trashed. I'm wondering if LPT1: is only passing 7 bits, playing > >with what it thinks are tabs, etc. I know the file is good because I can > > The same type of problem applies to TurboC/Pascal -- it thinks the printer is > a text device, so it bombs out on ^Zs... there are workarounds, although I > don't know the specifics of them. There are supposedly at least 2 ways around the problem in TC. One I do, one I think will work. Use the call biosprint(). While this makes your code non-portable, if you are using TC it probably already is. This is the one I use to get around the binary output problem. The other, untested, way is to do a setmode() on the output.
mat@emcard.UUCP (W Mat Waites) (01/11/91)
In article <1991Jan09.220846.15527@cavebbs.gen.nz> frank@cavebbs.gen.nz (Frank van der Hulst) writes: >In article <8280@emcard.UUCP> mat@emcard.UUCP (W Mat Waites) writes: >> >>I'm trying to print bitmaps files to a Laserjet via LPT1: and the image >>gets all trashed. I'm wondering if LPT1: is only passing 7 bits, playing >>with what it thinks are tabs, etc. I know the file is good because I can > >How are you doing it -- if you want to do it from DOS, try COPY/B FILE LPT1: >-- the /B tells DOS it's binary, and not to stop at a ^Z. Well, I have figured out the problem, and I mis-interpreted the symptoms. My files will print fine to a LJII, but screw up on a LJIII. I thought that the PCL stuff was compatible. BTW, I'm printing output from Gnuplot 2.0 pl 2 with the hpljii driver. Does anyone know why the LJIII should have trouble? Thanks, Mat -- W Mat Waites | Walking the wire is living, {gatech,emory}!emcard!mat | the rest is just waiting. - Wallenda
jimmy_t@verifone.com (01/12/91)
In article <8280@emcard.UUCP>, mat@emcard.UUCP (W Mat Waites) writes: > I'm trying to print bitmaps files to a Laserjet via LPT1: and the image > gets all trashed. I'm wondering if LPT1: is only passing 7 bits, playing > with what it thinks are tabs, etc. I know the file is good because I can > print it to a Laserjet from a Unix system (serial interface) and it works > fine. > > How can I get raw data through the parallel port? > If you are opening the LPT in a program as a DOS file, even if you tell DOS you want binary mode it may not give it to you. Here is the Microsoft C code I use to get around this problem. After I do a normal open of the file in binary mode, I call this routine with the handle returned by the open function: /**************************************************************************** Set Binary Mode *****************************************************************************/ void set_binary_mode (int target_handle) { int hand; union REGS r; /* get device info */ memset(&r, 0, sizeof(r)); r.h.ah = 0x44; r.h.al = 0x00; r.x.bx = target_handle; r.x.dx = 0; (void) int86(0x21, &r, &r); /* Check to see if DOS actually put device in character mode despite our request for binary mode. This is rumored to happen if you open a character device like LPT1: */ if ( (r.h.dl & 0x80) /* is it a character device? */ && !(r.h.dl & 0x20) /* in "cooked" mode */ ) { memset(&r, 0, sizeof(r)); r.h.ah = 0x44; r.h.al = 0x01; r.x.bx = target_handle; r.h.dh = 0x00; r.h.dl |= 0x20; /* set raw mode */ (void) int86(0x21, &r, &r); } } -- +------------------------------------+--------------------------------------+ | James H. Thompson | jimmy_t@verifone.com (Internet) | | VeriFone Inc. | uunet!verifone!jimmy_t (UUCP) | | 100 Kahelu Avenue | 808-623-2911 (Phone) | | Mililani, HI 96789 | | +------------------------------------+--------------------------------------+