Rainbow Electronics AT42QT1110-AZ - Manual (Page 34)

34
9570H–AT42–02/10
AT42QT1110-MZ/AT42QT1110-AZ
OUT_DETECTn: PWM to output when key n is “Out of Detect” (where n is 0–7). This PWM is
also output if the DETECT output is “disconnected” from the key (that is, “LED_n” in address 17
is set to 0), allowing the host to directly control the PWM output.
The values for the “IN_DETECTn” and “OUT_DETECTn” nibbles are listed in Table 7-12 .
Default IN_DETECTn value: 8 (100% PWM – on)
Default OUT_DETECTn value: 0 (0% PWM – off)
7.13 Address 16: LED Detect Hold Time
When a key is touched, if the “Detect” outputs and “Key to LED” options are enabled (see
Section 7.12 and Section 7.14 ), the corresponding “Detect” pin will output its “In-Detect” PWM
signal.
After the key touch is removed, the “Detect” output can be held at the “In-Detect” PWM signal for
a time before returning to the “Out of Detect” PWM signal. This allows a reasonable length of
time for an LED to be illuminated. The length of this time is controlled by the LED Detect Hold
Time. Valid values are in multiples of 16 ms.
Default value: 0 (0 ms)
Table 7-12. PWM Values
Value Meaning
0 0%
1 12.5%
2 25%
3 37.5%
4 50%
5 62.5%
6 75%
7 87.5%
8 100%
Table 7-13. LED Detect Hold Time
Address Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
16 LED_DETECT_HOLD_TIME