S1D13705F00A200 Epson, S1D13705F00A200 Datasheet - Page 89

• Manufacturer Part Number: S1D13705F00A200
• Manufacturer: Epson

Specifications of S1D13705F00A200

• Operating Supply Voltage (typ): 3.3/5V
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Package Type: TQFP
• Pin Count: 80
• Mounting: Surface Mount
• Operating Supply Voltage (min): 2.7V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / Rohs Status: Compliant

2: INITIALIZATION
for (int loop = 0; loop < 2; loop++)
{
}
// If we still can't hit the frame rate - throw an error.
{
}
2-4
if ((VNDP < 0) || (VNDP > 0x3F) || (HNDP < 32) || (HNDP > 280))
The following are the formulae for determining the frame rate of a panel. The formula for a single
passive or TFT panel is calculated as follows:
for a dual passive panel the formula is:
where : PCLK
In addition to varying the HNDP and VNDP times we can also select divider values which will
reduce CLKi to one half, one quarter up to one eight of the CLKi value. The example below is a
portion of a ’C’ routine to calculate HNDP and VNDP from a desired frame rate.
This routine first performs a formula rearrangement so that HNDP or VNDP can be solved. Start
with VNDP set to a small value. Loop increasing VNDP and solving the equation for HNDP until
satisfactory HNDP and VNDP values are found. If no satisfactory values are found then divide
CLKI and repeat the process. If a satisfactory frame rate still can’t be reached - return an error.
Note: Most passive (STN) panels are tolerant of nearly any combination of HNDP and VNDP values,
for (VNDP = 2; VNDP < 0x3F; VNDP += 3)
{
}
// Divide ClkI and try again.
// (Reg[02] allows us to dived CLKI by 2)
PCLK /= 2;
sprintf("ERROR: Unable to set the desired frame rate.\n");
exit(1);
however panel specifications generally specify only a few lines of vertical non-display period.
The S1D13705 is capable of generating a vertical non-display period of up to sixty-three lines.
This amount of VNDP is far too great a non-display period and will likely degrade display qual-
ity. Similarly, setting a large HNDP value may cause a degrade in image quality.
If possible the system should be designed such that VNDP values of 7 or less lines and HNDP
values of 20 or less characters can be selected.
// Solve for HNDP
if ((HNDP >= 32) && (HNDP <= 280))
{
}
HNDP = (PCLK / (FrameRate * (VDP + VNDP))) - HDP;
HDP
HNDP
VDP
VNDP
// Solve for VNDP.
VNDP = (PCLK / (FrameRate * (HDP + HNDP))) - VDP;
// If we have satisfied VNDP then we're done.
if ((VNDP >= 0) && (VNDP <= 0x3F))
FrameRate
FrameRate
= Pixel clock (in Hz)
= Horizontal Display Period (in pixels)
= Horizontal Non-Display Period (in pixels)
= Vertical Display Period (in lines)
= Vertical Non-Display Period (in lines)
goto DoneCalc;
=
=
---------------------------------------------------------------------------------------- -
-------------------------------------------------------------------------------------------------- -
2
HDP
HDP
EPSON
+
HNDP
+
HNDP
PCLK
PCLK
VDP
VDP
----------- -
+
2
VNDP
+
S1D13705F00A PROGRAMMING NOTES
VNDP
AND EXAMPLES (X27A-G-002-01)