Horizontal Generation Configuration Example

Programming the horizontal generation registers to the values shown in Table: Example Horizontal Generation Register Inputs will result in the video timing signal outputs shown in This Figure .

Notice that in Table: Example Horizontal Generation Register Inputs the Control Register bit 2 is set to enable generation, that all source selects are set to 1 to select the Generation Registers and that the polarity bits are all set to 1 to configure the outputs for active-High polarity.

Table 3-1: Example Horizontal Generation Register Inputs
Register Address	Register Name	Value
0x0060	Generator Active Size	0x0003_0003
0x0070	Generator HSize	0x0000_0007
0x0078	Generator HSync	0x0005_0004
0x0068	Generator Encoding	0x0000_0000
0x006C	Generator Polarity	0x0000_003f
0x0000	Control	0x01ff_ff07

Figure 3-3: Generated Horizontal Timing
X-Ref Target - Figure 3-3

IMPORTANT: All signals are shown active-High. The polarities of the output signals can be changed at any time via the GENERATOR POLARITY REGISTER (0x006C).

The following C code shows how to configure the register values in Table: Example Horizontal Generation Register Inputs using the Video Timing Controller driver.

XVtc Vtc; /* Device driver instance */

XVtc_Signal SignalCfg; /* VTC Signal configuration */

XVtc_Polarity Polarity; /* Polarity configuration */

XVtc_SourceSelect SourceSelect;/* Source Selection configuration */

XVtc_Config *VtcCfgPtr;

VtcCfgPtr = XVtc_LookupConfig(VTC_DEVICE_ID);

XVtc_CfgInitialize(&Vtc, VtcCfgPtr, VtcCfgPtr->BaseAddress);

/* Setup the VTC Source Select config structure. */

/* 1=Generator registers are source */

/* 0=Detector registers are source */

memset((void *)&SourceSelect, 0, sizeof(SourceSelect));

SourceSelect.VBlankPolSrc = 1;

SourceSelect.VSyncPolSrc = 1;

SourceSelect.HBlankPolSrc = 1;

SourceSelect.HSyncPolSrc = 1;

SourceSelect.ActiveVideoPolSrc = 1;

SourceSelect.ActiveChromaPolSrc= 1;

SourceSelect.VChromaSrc = 1;

SourceSelect.VActiveSrc = 1;

SourceSelect.VBackPorchSrc = 1;

SourceSelect.VSyncSrc = 1;

SourceSelect.VFrontPorchSrc = 1;

SourceSelect.VTotalSrc = 1;

SourceSelect.HActiveSrc = 1;

SourceSelect.HBackPorchSrc = 1;

SourceSelect.HSyncSrc = 1;

SourceSelect.HFrontPorchSrc = 1;

SourceSelect.HTotalSrc = 1;

/* Setup the VTC Polarity config structure. */

memset((void *)&Polarity, 0, sizeof(Polarity));

Polarity.ActiveChromaPol = 1;

Polarity.ActiveVideoPol = 1;

Polarity.VBlankPol = 1;

Polarity.VSyncPol = 1;

Polarity.HBlankPol = 1;

Polarity.HSyncPol = 1;

/* Setup the VTC Signal config structure. */

memset((void *)&SignalCfg, 0, sizeof(XVtc_Signal));

SignalCfg.OriginMode = 1;//Set Frame Origin to Start of Active Video

SignalCfg.HTotal = 7;

SignalCfg.HActiveStart = 0;

SignalCfg.HFrontPorchStart = 3;// Active Video Width

SignalCfg.HSyncStart = 4;// Active Video Width + FP Width

SignalCfg.HBackPorchStart = 5;// Active Video Width + FP Width + Sync Width

SignalCfg.V0Total = 7;

SignalCfg.V0ChromaStart = 0;

SignalCfg.V0ActiveStart = 0;

SignalCfg.V0FrontPorchStart = 3;// Active Video Height

SignalCfg.V0SyncStart = 4;// Active Video Height + FP_Width

SignalCfg.V0BackPorchStart = 5;// Active Video Height + FP Width + Sync Width

/* Write VTC config to HW */

XVtc_RegUpdate(&VTC);

XVtc_SetPolarity(&Vtc, &Polarity);

XVtc_SetGenerator(&Vtc, &SignalCfg);

XVtc_SetSource(&Vtc, &SourceSelect);

/* Enable VTC Generator */

XVtc_Enable Generator(&Vtc);

Horizontal Generation Configuration Example - 6.2 English

Video Timing Controller Product Guide (PG016)