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Type out just a little of status register 1.

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This commit is contained in:
Thomas Harte 2023-01-30 20:20:33 -05:00
parent 8f20cb93e9
commit bc4c54800e
1 changed files with 10 additions and 1 deletions
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11
Components/9918/Implementation/9918.cpp
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@ -1020,7 +1020,16 @@ uint8_t Base<personality>::read_register() {
default:
case 0: break;
case 1: LOG("TODO: Yamaha status 1"); break;
case 1:
// b7 = light pen; set when light is detected, reset on read;
// or: mouse button 2 currently down.
// b6 = light pen button or mouse button 1.
// b5–b1 = VDP identification (1 = 9938; 2 = 9958)
// b0 = set when the VDP reaches the line provided in the line interrupt register.
// Reset upon read.
return
personality == Personality::V9938 ? 0x2 : 0x4;
break;
case 2: {
// b7 = transfer ready flag (i.e. VDP ready for next transfer)