Beiträge von Snoopy im Thema „Where did MEGA 65 get the characters from?“

    So not directly the ROM is being used as the source of "ROM charset". Now what I am not sure, how it changed lately (Xemu uses an older Hyppo ....).

    Thanks for your answer!

    The latest bitstream don't use the old "CHARROM.M65" anymore.

    This is the content of my current SD card for the Nexys board:

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    As described Bitte melde dich an, um diesen Link zu sehen. and below and Bitte melde dich an, um diesen Link zu sehen., I'm searching for the reason, why MEGA 65 (in my case: Nexys board with new bitstream "nexys4ddr-widget-20200624.10-138-hd-27b1f22+DIRTY.bit") or xmega65 of Xemu emulator doesn't use the character datas of the C65 ROM for display them?

    In Bitte melde dich an, um diesen Link zu sehen. of the latest C65 ROM, I had change some char datas in the ROM for displaying german umlauts and the Euro symbol.

    Let me show the problem with some screenshots:

    As an example to show the problem, I want to display the german "Ä" and therefore I change the char data in ROM from position $09380 to $09387 - for CHR$(176) - with $66, $18, $3C, $66, $7E, $66, $66, $00.

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    Starting xc65 of Xemu and let me see the CHR$(176) the "Ä" is correctly shown:

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    Using MONITOR to see the ROM memory of position $9380 (bank 2) shows the changed values for the "Ä" character:

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    Then I do the same with xmega65 of Xemu the CHR$(176) is the symbol which is stored in the unpatched original ROM:

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    Using MONITOR to look at the ROM value $9380 in bank 2 I can see, that the changed char values are stored correct in the ROM:

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    It's the same using the Nexys board with bitstream "nexys4ddr-widget-20200624.10-138-hd-27b1f22+DIRTY.bit".

    With MEGA 65 the char datas for CHR$(176) are obviously not from the (patched) C65 ROM.

    But where do MEGA 65 gets the datas for displaying the character from? :gruebel