BSP Developer's Guide

VxWorks 5.5
BSP Developer’s Guide
driver would not reside in the target/src/drv directory but in a BSP-specific
directory (from which the BSP’s sysLib.c can include the driver when needed).
F.2 Serial Drivers
Generic serial drivers reside in the directory target/src/drv/serial. Included in this
directory is templateSerial.c and its corresponding header file, templateSerial.h.
These files contain very detailed information on the design and construction of a
typical serial driver. When writing a serial driver, base the driver on this template,
then modify the BSP’s sysLib.c or sysSerial.c files to include the driver as needed.
NOTE: Serial drivers are provided for backward compatibility with VxWorks 5.2
and earlier. All Tornado-era BSPs should instead use the SIO drivers.
To manage information about a serial device, sysLib.c uses a device descriptor.
This device descriptor also encapsulates board-specific information. For example,
it typically includes the frequency of the clock and the addresses of the registers,
although the details are dictated by the device in question. In sysLib.c, the serial
device descriptor is declared outside the function definitions as:
TY_CO_DEV tyCoDv [NUM_TTY]; /* structure for serial ports */
This array is initialized at run-time in sysHwInit( ). The TY_CO_DEV structure is
defined in the device header file (for example, target/h/drv/serial/z8530.h). The
following members of the TY_CO_DEV structure are common to all serial drivers:
tyDev
Required by tyLib, the VxWorks tty driver support library.
created
A flag that must be initialized to FALSE in sysHwInit( ).
numChannels
Used for parameter checking.
The following macros must be defined for all BSPs:
NUM_TTY
Defines the number of serial channels supported. In configAll.h, the default
defined as 2. To override the default, first undefine then define NUM_TTY in
config.h. If there are no serial channels, define NUM_TTY as NONE.
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