PPC (4) | Special files and drivers | Unix Manual Pages

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PPC (4) | Special files and drivers | Unix Manual Pages | :man▋

NAME

ppc - Parallel Port Chipset driver

Synopsis
Description
Supported flags
Supported chipsets
Adding support to a new chipset
See Also
History
Authors
Bugs

SYNOPSIS

.Cd "device ppc"

In /boot/device.hints:
.Cd hint.ppc.0.at= "isa"
.Cd hint.ppc.0.irq= "7"

For one or more PPBUS busses:
.Cd "device ppbus"

DESCRIPTION

The ppc driver provides low level support to various parallel port chipsets for the ppbus(4) system.

During the probe phase, ppc detects parallel port chipsets and initializes private data according to their operating mode: COMPATIBLE, NIBBLE, PS/2, EPP, ECP and other mixed modes. If a mode is provided at startup through the flags variable of the boot interface, the operating mode of the chipset is forced according to flags and the hardware supported modes.

During the attach phase, ppc allocates a ppbus structure, initializes it and calls the ppbus attach function.

Supported flags

	bits 0-3: chipset forced mode(s) PPB_COMPATIBLE 0x0/* Centronics compatible mode / PPB_NIBBLE 0x1/ reverse 4 bit mode / PPB_PS2 0x2/ PS/2 byte mode / PPB_EPP 0x4/ EPP mode, 32 bit / PPB_ECP 0x8/ ECP mode */ And any mixed values.
	bit 4: EPP protocol (0 EPP 1.9, 1 EPP 1.7)
	bit 5: activate IRQ (1 IRQ disabled, 0 IRQ enabled)
	bit 6: disable chipset specific detection
	bit 7: disable FIFO detection