Difference between revisions of "OSBYTE &71"
m (1 revision) |
(update) |
||
Line 2: | Line 2: | ||
OSBYTE &71 (113) - Select Main/Shadow for Display hardware | OSBYTE &71 (113) - Select Main/Shadow for Display hardware | ||
− | + | X=0 Use whatever the default for the current mode is | |
− | The value of X | + | X=1 Use main memory |
+ | X=2 Use shadow memory | ||
+ | (Risc OS 1.00) | ||
+ | The value of X can be greater than 2 as well, and instructs the video | ||
+ | hardware to use the bank at screenbase+(X*modesize) | ||
+ | |||
+ | This call specifies which bank of memory the Master video display hardware | ||
+ | access. Using this and [[OSBYTE &70]] a program can use the VDU to write to | ||
+ | one bank of memory while the other is being displayed. | ||
==See Also== | ==See Also== | ||
+ | * [[OSBYTE &6C]] - Select Master shadow memory | ||
+ | * [[OSBYTE &6F]] - Select BBC B shadow memory | ||
+ | * [[OSBYTE &70]] - Select memory for Master VDU access | ||
+ | * [[OSBYTE &71]] - Select memory for Master video display | ||
+ | * [[OSBYTE &72]] - Select future use of shadow memory | ||
+ | * [[OSBYTE &73]] - Select shadow bank | ||
+ | * [[OSBYTE &74]] - Check for Solidisk shadow memory | ||
+ | * [[Paging in video memory]] | ||
* http://mdfs.net/Docs/Comp/BBC/Osbyte00 | * http://mdfs.net/Docs/Comp/BBC/Osbyte00 | ||
− | [[User: | + | [[User:WikiSysop|WikiSysop]] ([[User talk:WikiSysop|talk]]) 13:33, 8 March 2015 (UTC) |
Revision as of 14:33, 8 March 2015
OSBYTE &71 (113) - Select Main/Shadow for Display hardware
X=0 Use whatever the default for the current mode is X=1 Use main memory X=2 Use shadow memory (Risc OS 1.00) The value of X can be greater than 2 as well, and instructs the video hardware to use the bank at screenbase+(X*modesize)
This call specifies which bank of memory the Master video display hardware access. Using this and OSBYTE &70 a program can use the VDU to write to one bank of memory while the other is being displayed.
See Also
- OSBYTE &6C - Select Master shadow memory
- OSBYTE &6F - Select BBC B shadow memory
- OSBYTE &70 - Select memory for Master VDU access
- OSBYTE &71 - Select memory for Master video display
- OSBYTE &72 - Select future use of shadow memory
- OSBYTE &73 - Select shadow bank
- OSBYTE &74 - Check for Solidisk shadow memory
- Paging in video memory
- http://mdfs.net/Docs/Comp/BBC/Osbyte00