CP60 and CP60 Plus Service Manual
2-35
Reader to Card Communication
The reader communicates with the card by sending an amplitude modulated
signal at 13.56 MHz. The modulation variant depends on the class of card. A
Type-A card uses 100% Amplitude Shift Keying (ASK100%). A Type-B card uses
ASK10% modulation. These two variants are shown in the graphics above.
The benefit of ASK100 is that it is more immune to noise and errors because there
is a strong difference in amplitude at bit transitions. The drawback to this is that
the card doesn’t receive power during the low cycle of the modulation. The card
doesn’t turn off during these times, but the effect is that less overall (average)
power is being transmitted to the card.
ASK10 provides more power to the card because the modulated signal remains
within 10% of the maximum amplitude. The tradeoff is that the difference
between high and low amplitudes is minimal. This can lead to slightly more data
transmission errors.
Summary of Contents for CP60
Page 1: ...Datacard CP60 and CP60 Plus Card Printers Service Manual May 2007 Part No 539358 002 Rev C ...
Page 12: ...1 4 Introduction ...
Page 14: ...2 2 Theory of Operation Printer Components Functional Block Diagram ...
Page 19: ...CP60 and CP60 Plus Service Manual 2 7 LCD Menu Diagram ...
Page 50: ...2 38 Theory of Operation ...
Page 124: ...5 40 Adjustments ...
Page 128: ...6 4 Removal and Replacement Front Wire Routing ...
Page 129: ...CP60 and CP60 Plus Service Manual 6 5 Duplex and Printhead Wire Routing ...
Page 130: ...6 6 Removal and Replacement Functional Block Diagram ...