lp(7)
NAME
lp − driver for parallel port
SYNOPSIS
include <sys/bpp_io.h>
fd = open("/dev/lpn", flags);
name=lp
class=sysbus
ioaddr=0x378 interrupts=3,7;
name=lp
class=sysbus
ioaddr=0x278 interrupts=3,5;
AVAILABILITY
x86
DESCRIPTION
The lp driver provides the interface to the parallel ports used by printers for x86 systems. The lp driver is implemented as a STREAMS device. Up to three parallel ports can be accessed by the driver. The lp driver accesses the /kernel/drv/lp.conf file for specifications about these parallel ports. The specifications include:
name
class
ioaddr The I/O port base address for this port.
interrupts The IRQ level of the port. interrupts is analogous to intr.
For more information about lp.conf, refer to sysbus(4).
IOCTLS
BPPIOC_TESTIO Test transfer readiness. This command checks to see if a read or write transfer would succeed based on pin status. If a transfer would succeed, 0 is returned. If a transfer would fail, −1 is returned, and errno is set to EIO. The error status can be retrieved using the BPPIOC_GETERR ioctl() call.
BPPIOC_GETERR Get last error status. The argument is a pointer to a struct bpp_error_status. See below for a description of the elements of this structure. This structure indicates the status of all the appropriate status bits at the time of the most recent error condition during a read(2) or write(2) call, or the status of the bits at the most recent BPPIOC_TESTIO ioctl(2) call. The application can check transfer readiness without attempting another transfer using the BPPIOC_TESTIO ioctl().
Error Pins Structure
This structure and symbols are defined in the include file <sys/bpp_io.h>:
struct bpp_error_status {
chartimeout_occurred;/∗ Not use ∗/
charbus_error;/∗ Not use ∗/
u_charpin_status; /∗ Status of pins which could
∗ cause an error ∗/
};
/∗ Values for pin_status field ∗/
#defineBPP_ERR_ERR0x01/∗ Error pin active ∗/
#defineBPP_SLCT_ERR0x02/∗ Select pin active ∗/
#defineBPP_PE_ERR0x04/∗ Paper empty pin active ∗/
Note: Other pin statuses are defined in <sys/bpp_io.h>, but BPP_ERR_ERR, BPP_SLCT_ERR and BPP_PE_ERR are the only ones valid for the x86 lp driver.
ERRORS
EIO A BPPIOC_TESTIO ioctl() call is attempted while a condition exists that would prevent a transfer (such as a peripheral error).
EINVAL An ioctl() is attempted with an invalid value in the command argument.
FILES
/kernel/drv/lp.conf
configuration file for lp driver. For a description of each field, refer to sysbus(4).
SEE ALSO
DIAGNOSTICS
"lp_attach: cannot add intr."
An invalid intr= or interrupts= property has been specified in the /kernel/drv/lp.conf file.
NOTES
A read operation on a bi-directional parallel port is not supported.
SunOS 5.4 — Last change: 9 Dec 1993