Thursday, December 20, 2012
Added some more LDP-1450 commands
In order to add support for text overlay to my LDP-1450 code, I decided to get Dexter working with Dragon's Lair 2. As it turns out, Dragon's Lair 2 sends a bunch of commands upon bootup to the LDP-1450 to make sure it is in a sane default state. I don't actually have to do any processing of these commands (like I said they just put the player into a default state which I am already in) but I do need to acknowledge them anyway. The commands I now acknowledge include: 0x62 (motor on) 0x6E (CX on) 0x27 (video on) 0x28 (picture stop code enable) 0x55 (frame mode) 0x24 (audio on) Dragon's Lair 2 also issues a 0x67 (status inquiry) command which I do not have documentation for. I confirmed (by using my real LDP-1450) that when the player is playing, it will return 0x80 0x00 0x10 0x00 0x01 and when the player is paused (still frame mode) it will return 0x80 0x00 0x10 0x00 0x20. I can't think of what other state the player possibly could be in except maybe in the middle of a search and playing backward or at a different speed. I am not sure how much I need to explore this since DL2 probably just wants to know if the disc is playing or paused and other games probably don't care at all. I guess this is one thing I can leave barely implemented for now and add richer support for later if it becomes required. After adding the bare bones status inquiry response, I can get wookin' on the text overlay stuff.