HCS410 datasheet(12/46 Pages) MICROCHIP

12 / 46 page

HCS410

DS40158F-page 12

2.3.9

LED OUTPUT

The S2/LED line can be used to drive a LED when the

HCS410 is transmitting. If this option is enabled in the

configuration word the S2 line is driven high periodi-

cally when the HCS410 is transmitting as shown in

Figure 2-14. The LED output operates with a 30 ms on

and 480 ms off duty cycle when the supply voltage is

above the level indicated by the VLOW bit in the config-

uration word. When the supply voltage drops below the

voltage indicated by the VLOW bit the HCS410 will indi-

cate this by turning the LED on for 200ms at the start of

a transmission and remain off for the rest of the trans-

mission.

2.3.10

DELAYED INCREMENT

The HCS410 has a delayed increment feature that

increments the counter by 12, 20 seconds after the last

button press occurred. The 20-second time-out is reset

and the queue counter will increment if another press

occurs before the 20 seconds expires. The queue

counter is cleared after the buttons have been released

for more than 2 seconds. Systems that use this feature

will circumvent the latest jamming-code grabbing

attackers.

2.3.11

OTHER CONFIGURABLE OPTIONS

Other configurable code hopping options include an

• Transmission-rate selection

• Extended serial number.

These are described in more detail in Section 3.7.

FIGURE 2-14: LED INDICATION DURING TRANSMISSION

200 ms

480 ms

30 ms

S Input

LED

VDD = VLOW Level

LED

VDD < VLOW LEVEL

40158F.book Page 12 Wednesday, June 1, 2011 10:36 AM

HCS410 数据表(PDF) 12 Page - Microchip Technology

HCS410 数据表(HTML) 12 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46

数据表下载