How can you please put the screen in ASM to # 4000 and make it visible?

[funkheld]

Hi good afternoon.
How can you please put the screen in ASM to # 4000 and make it visible?


How can you please set the screen in ASM to # 4000 and make it invisible,
so that from # c000 you can describe area # 4000?


Thank you.
greeting

[roudoudou]

Code Select Expand

ld bc,#BC00+12
out (c),c
ld bc,#BD10
out (c),c
register 12 at #10 instead of #30 means video adress at #4000 instead of #C000

you should read cpcwiki CRTC documentation or quasar.cpcscene.net technical section to understand video structure and CRTC register usage

http://www.cpcwiki.eu/index.php/CRTC

[Nich]

You can also do this using the firmware:

Code Select Expand

ld a,#40
call #BC08

The A register contains the high byte of the start address of the screen.

EDIT: The correct address for the CALL is #BC08, not #BC06!

[funkheld]

Hi good afternoon.
Thanks for your help.


I can not switch to # 4000 and then
at # 4000 also the text entries to make.


Thank you.
greeting