Samsung FACSIMILE SF40 Service Manual page 32

1) Printer Control
Fig. 10 is the simplified printer strobe generation block diagram.
All timing in Fig. 9 is driven from the CPUCLK.
PRTSTBPERIOD
PrtDotPerlod
AND PRTSTBON
PCLK GEN
PCLK
i PCLK GEN —
i PDAT
a PCLK GEN
PLAT
REGISTER
The first scalar in the CPUCLK processing chain is PrtDotscaler, with its scaling controlled by register PrDotPeriod.
[Fig. 10]
Ri
THDI
To Thermal Head
Thermal Head
R2 Rt(T)
i a
R1 and R2 can be caculated from the following formulas :
R2 = [15Rt(T1) * Rt(T2)] / [Rt(T1)-16Rt(T2)]
Ri = 0.25 * [R2 * Rt(T1)] /[R2 + Rt(T1)]
Where :
T1 - min temperature
T2 - max temperature
[Fig. 11]
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