
18: CLOCKING
1-170
EPSON
S1D13806 SERIES HARDWARE FUNCTIONAL
SPECIFICATION (X28B-A-001-03)
18.1.2 CRT Frame Rate Calculation
The maximum CRT frame rate is calculated using the following formula.
Where:
CPCLKmax = maximum CRT pixel clock frequency
CVDP
= CRT Vertical Display Height
= REG[057h] bits [1:0], REG[056h] bits [7:0] + 1
CVNDP
= CRT Vertical Non-Display Period
= REG[058h] bits [6:0] + 1
CHDP
= CRT Horizontal Display Width
= ((REG[050h] bits [6:0]) + 1)
× 8Ts
CHNDP
= CRT Horizontal Non-Display Period
= ((REG[052h] bits [5:0]) + 1)
× 8Ts
Ts
= minimum CRT pixel clock (CPCLK) period
max. CRT Frame Rate
CPCLKmax
CHDP CHNDP
+
()
CVDP CVNDP
+
()
×
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