Controller - Institute of Transportation Engineers

4.2.7.2.6
The device shall provide four input buffering modes as follows:
1.Line - characters are buffered up to and including a programmable termination
character.
2. Fixed - a fixed specific number of characters is buffered by the driver (1 @ 1200bps, 2
@ 2400bps, 4 @ 4800 bps, 8 @ 9600 bps, and 16 @ 19200 bps & above)
3.Timed- characters are buffered until a programmable inter-character time out occurs.
4. Raw – characters are unbuffered and delivered to the task as received.
4.2.7.2.7
Line, Fixed, and Timed Modes shall be capable of being used together. Raw mode shall
disable all other buffering modes.
4.2.7.2.8
Device drivers compliant with the OS-9 SCFMAN shall be provided for CPU Activity
LED Indicator and Day Light Savings time correction features. The descriptor names
shall be as follows:
led
dstclock
= access to CPU Activity LED Indicator
= access to Daylight Savings Time Clock correction
The standard OS-9 SCFMAN library calls and their functions are as follows:
error_code _os_open (char *desc_name, path_id *path); //open descriptor for command
error_code _os_close (path_id path);
//close descriptor
error_code _os_write (path_id path, void *value, 1); //set value or function
*value = 1, turn led on or turn DLSclock feature on (default)
*value = 0, turn led off or turn DLSclock feature off
error_code _os_read (path_id path, void *value, 1); //get current state
4.2.7.2.9 Time-of-Day (TOD) Clock
The OS-9 operating system’s TOD Clock shall be driven by the LINESYNC derived OS-
9 Operating System TICK Timer. The device shall provide the following features to
support the TOD operation and synchronization.
4.2.7.2.9.1
Leap Year and Daylight Savings Time (DST) Adjustments - The OS-9 System clock /
calendar shall automatically be adjusted to account for DST and leap years. A SCFMAN
driver shall be provided to enable/disable the automatic DST adjustment.
Standard for the ATC – Type 2070 March 29, 2001
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