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CnpV
Programmer's Reference Manuals
» Part 1 - Introduction
» Vectors
» Software Vector Numbers
» CnpV
Count/Purge Vector (22)
| Entry | |
|---|---|
| R1 | Buffer number |
| V flag and C flag encode the action: | |
| V flag = 0, C flag = 0: Return number of entries | |
| V flag = 0, C flag = 1: Return amount of free space | |
| V flag = 1: Flush buffer | |
| Exit | |
|---|---|
| R0 | Corrupted |
| R1-R2 | Preserved (if purge), else; |
| R1 | Count AND &FF |
| R2 | Count >> &FF |
Use
This vector is called to count the number of entries or spaces in a buffer, or to flush the contents of a buffer.
Notes
If called via OS_CallAVector then interrupts must be disabled first.