# LCD的参数适配 LCD的参数和其他外设一样在fex文件里修改 像分辨率和画布偏移之类的，都在以下字段： ~~~ lcd_x = 800 lcd_y = 480 lcd_dclk_freq = 33 lcd_hv_hspw = 23 lcd_hbp = 46 lcd_ht = 1055 lcd_hv_vspw = 1 lcd_vbp = 10 lcd_vt = 1050 ~~~ 例如改成1024*768 ~~~ lcd_x = 1024 lcd_y = 768 lcd_dclk_freq = 65 lcd_hv_vspw = 6 lcd_hv_hspw = 136 lcd_hbp = 180 lcd_ht = 1344 lcd_vbp = 29 lcd_vt = 1612 ~~~ 在超分辨率使用时，注意以下代码（具体查看源码）的限制 ~~~ /* hv panel, CPU panel and ttl panel */ if (info->lcd_if == 0 || info->lcd_if == 1 || info->lcd_if == 2) { /* MHz */ if (lcd_dclk_freq > 2000000 && lcd_dclk_freq <= 297000000) { /* divider for dclk in tcon0 */ *divider = 297000000 / (lcd_dclk_freq); pll_freq = lcd_dclk_freq * (*divider); } else { return -1; } } ~~~ 以下是未整理的移植时的手记，可以参考： ~~~ drivers/video/sunxi_display.c video_hw_init drivers/video/videomodes.c int video_get_params (struct ctfb_res_modes *pPar, char *penv) mode: 0~9 640*480~1920*1200,默认0 x: y: refresh: le:left_margin ri:right_margin up:upper_margin lo:lower_margin hs:hsync_len vs:vsync_len sync:sync #define FB_SYNC_HOR_HIGH_ACT 1 /* horizontal sync high active */ #define FB_SYNC_VERT_HIGH_ACT 2 /* vertical sync high active */ #define FB_SYNC_EXT 4 /* external sync */ #define FB_SYNC_COMP_HIGH_ACT 8 /* composite sync high active */ #define FB_SYNC_BROADCAST 16 /* broadcast video timings */ /* vtotal = 144d/288n/576i => PAL */ /* vtotal = 121d/242n/484i => NTSC */ #define FB_SYNC_ON_GREEN 32 /* sync on green */ vmode:vmode #define FB_VMODE_NONINTERLACED 0 /* non interlaced */ #define FB_VMODE_INTERLACED 1 /* interlaced */ #define FB_VMODE_DOUBLE 2 /* double scan */ #define FB_VMODE_ODD_FLD_FIRST 4 /* interlaced: top line first */ pclk:pixclock pclk_khz:pixclock_khz depth: 色深 bp = mode->hsync_len + mode->left_margin; 10 (43-10)=33 total = mode->xres + mode->right_margin + bp; 480 8 43 bp = mode->vsync_len + mode->upper_margin; 10 (12-10)=2 total = mode->yres + mode->lower_margin + bp; 272 4 12 x:480,y:272,depth:18,pclk_khz:9000,le:33,ri:8,up:2,lo:4,hs:10,vs:10,sync:0,vmode:0 x:800,y:480,depth:18,pclk_khz:33000,le:100,ri:170,up:35,lo:2,hs:10,vs:10,sync:0,vmode:0 Setting up a 480x272 lcd console (overscan 0x0) 背光闪了下 drivers/video/sunxi_display.c video_hw_init sunxi_mode_set(mode, fb_dma_addr); static void sunxi_lcdc_backlight_enable(void) ~~~ hsync + hbp(back porch) + X len + hfp(front porch) hb(H blanking) hbp相当于画面在画布中的偏移， 屏幕在左边和上边都有一部分不能显示的等待区域，要调整hbp移出这部分， 否则会有一部分在屏幕外不显示 hsync值只要大于1即可