.\"******************************************************************* .\" .\" This file was extracted from hal/drivers/serport.comp using halcompile.g. .\" Modify the source file. .\" .\"******************************************************************* .TH SERPORT "9" "2024-03-13" "LinuxCNC Documentation" "HAL Component" .SH NAME serport \- Hardware driver for the digital I/O bits of the 8250 and 16550 serial port. .SH SYNOPSIS .B loadrt serport io=\fIaddr[,addr...]\fR .PP The pin numbers refer to the 9-pin serial pinout. Keep in mind that these ports generally use rs232 voltages, not 0/5V signals. Specify the I/O address of the serial ports using the module parameter \fBio=\fIaddr[,addr...]\fR. These ports must not be in use by the kernel. To free up the I/O ports after bootup, install setserial and execute a command like: .RS sudo setserial /dev/ttyS0 uart none .RE but it is best to ensure that the serial port is never used or configured by the Linux kernel by setting a kernel commandline parameter or not loading the serial kernel module if it is a modularized driver. .SH FUNCTIONS .TP \fBserport.\fIN\fB.read\fR .TP \fBserport.\fIN\fB.write\fR .SH PINS .TP .B serport.\fIN\fB.pin-1-in\fR bit out \fR Also called DCD (data carrier detect); pin 8 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-6-in\fR bit out \fR Also called DSR (data set ready); pin 6 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-8-in\fR bit out \fR Also called CTS (clear to send); pin 5 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-9-in\fR bit out \fR Also called RI (ring indicator); pin 22 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-1-in-not\fR bit out \fR Inverted version of pin-1-in .TP .B serport.\fIN\fB.pin-6-in-not\fR bit out \fR Inverted version of pin-6-in .TP .B serport.\fIN\fB.pin-8-in-not\fR bit out \fR Inverted version of pin-8-in .TP .B serport.\fIN\fB.pin-9-in-not\fR bit out \fR Inverted version of pin-9-in .TP .B serport.\fIN\fB.pin-3-out\fR bit in \fR Also called TX (transmit data); pin 2 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-4-out\fR bit in \fR Also called DTR (data terminal ready); pin 20 on the 25-pin serial pinout .TP .B serport.\fIN\fB.pin-7-out\fR bit in \fR Also called RTS (request to send); pin 4 on the 25-pin serial pinout .SH PARAMETERS .TP .B serport.\fIN\fB.pin-3-out-invert\fR bit rw \fR .br .ns .TP .B serport.\fIN\fB.pin-4-out-invert\fR bit rw \fR .br .ns .TP .B serport.\fIN\fB.pin-7-out-invert\fR bit rw \fR .br .ns .TP .B serport.\fIN\fB.ioaddr\fR u32 r \fR .SH LICENSE GPL