Changes

V9990

957 bytes added, 15:15, 10 February 2019
/* POINT */
* Always set NX,NY before using LMMV especially in P1 mode. If you don't do this then the command may hang.
 
==== CMMC ====
 
* Data written is byte by byte and is 1 bit per pixel. If bit value is 0, then background colour will be written, otherwise foreground colour will be written.
 
* Font is defined left to right, top to bottom, line by line. It doesn't appear to follow the same form as Kanji ROM.
 
* Pixels are written according to physical vram. e.g. e.g. in 8bpp mode, x=0 and bit value is 1, foreground low byte is written, x = 1 and bit value is 1, then foreground high byte is written.
 
* For LOP, SC comes from background colour or foreground colour.
 
==== CMMM ====
 
* This is similar to CMMC except data is read from VRAM and not from the CPU.
 
==== CMMK ====
 
* This command is similar in operation to CMMM.
 
* This command will operate without Kanji ROM.
 
* It is not clear where the pixel data is coming from when no Kanji ROM is connected. It is not forced to ff or 0. It almost looks like it is reading it from VRAM using the Kanji ROM address.
==== POINT ====
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