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This version of this document is no longer maintained. For the latest documentation, see http://www.qnx.com/developers/docs. |
PSC UART serial communications manager for MPC5200 (QNX Neutrino)
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You must be root to start this driver. |
devc-serpsc [options] port[^shift],intr... &
PowerPC
The options are position-dependent and affect the subsequent ports.
The order in which you specify the -E or -e, and -S or -s options matters:
Options | Mode | Software flow control |
---|---|---|
-e | Edited | Enabled |
-S -e | Edited | Enabled |
-e -S | Edited | Disabled |
-E | Raw | Disabled |
-s -E | Raw | Disabled |
-E -s | Raw | Enabled |
...
The default shift is 0.
The devc-serpsc manager is a small serial device manager for QNX Neutrino. It can support any number of serial ports using PSC UART driver for MPC5200. Each device can be assigned its own interrupt, or share an interrupt if the hardware supports interrupt sharing. You must specify an I/O port and IRQ.
The serial driver's priority floats to the priority of the client. All internal events are processed at priority 24 (inherited from the internal pulse). The event handling priority is hard coded and isn't configurable by any of the options listed. (The driver's main.c program would need modification in order to change the priority).
When the driver talks to a client application, it's running at the priority of the client. All other processing takes place either at priority 24r or at interrupt time.
Each device is given a name in the pathname space of /dev/sern, where n starts at 1 (unless changed via the -u option) and increases.
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If your application uses /dev/console,
you should create a link from it to one of
/dev/ser1, /dev/ser2, ... by adding
a line like this to the buildfile used by mkifs:
[type=link] /dev/console = /dev/ser1 |
All devices are fully interrupt driven and by default support standard hardware flow control on input and output (RTS/CTS). This can be disabled by the -F option.
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Hardware flow control isn't supported in edited mode. |
A read request by default returns when at least 1 character is available. To increase efficiency, you can control three parameters to control when a read is satisfied:
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If the Min value is greater than the size of the input buffer, the Min value is clipped to the size of the buffer. To avoid this, the size of the input buffer can be changed with the -I option. |
These parameters are set using library routines (see tcgetattr(), tcsetattr(), readcond() and TimerTimeout() in the Library Reference).
The devc-serpsc manager supports both raw and edited modes, making it a real tty device.
The following fields and flags are supported in the termios structure:
Field | Supported flags |
---|---|
c_cc | All characters |
c_iflag | BRKINT ICRNL IGNBRK IXON |
c_oflag | OPOST |
c_cflag | CLOCAL CSIZE CSTOPB PARENB PARODD |
c_lflag | ECHO ECHOE ECHOK ECHONL ICANON IEXTEN ISIG NOFLSH |
Start devc-serpsc for the Freescale Lite5200 EVB:
devc-serpsc -c 132000000 -u 1 -e -F -S -b 115200 0xf0002000,65 &
Start devc-serpsc for the Freescale Total5200 SDP:
devc-serpsc -c 132000000 -u 3 -e -F -S -b 115200 0xf0002400,67 &
Character I/O drivers (devc-*) in the Utilities Summary
Connecting Hardware in the Neutrino User's Guide
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