HCS512_11 Datasheet, PDF (11/34 Pages) Microchip Technology – KEELOQ® Code Hopping Decoder system and high security

FIGURE 6-2: PROGRAMMING WAVEFORMS
HCS512
MCLR
T_PS
CLK
(Clock)
DAT
(Data)
T_PH1
T_PH2
T_CKL
T_CKH
T_ACK
T_ACKH
Bit0 Bit1
Bit78 Bit79
Ack
Enter Program Mode
80-bit Data Package
Acknowledge
pulse
TABLE 6-4: PROGRAMMING TIMING REQUIREMENTS
Parameter
Symbol
Min.
Program mode setup time
Hold time 1
Hold time 2
Clock High Time
Clock Low Time
Acknowledge Time
Acknowledge duration
Note: FOSC equals 4 MHz.
TPS
TPH1
TPH2
TCKH
TCKL
TACK
TACKH
1
8
0.05
0.05
0.050
—
1
Max.
64
128
320
320
320
80
—
Units
ms
ms
ms
ms
ms
ms
ms
© 2011 Microchip Technology Inc.
DS40151E-page 11