AT42QT1111-AU_14 Datasheet, PDF (23/50 Pages) ATMEL Corporation – 11-key QTouch Touch Sensor IC

6. Report Requests
6.1 Introduction
The host can request reports from the QT1111, as summarized in Table 6-1.
Table 6-1. Report Requests
Command
Send First Key
Send All keys
Device Status
EEPROM CRC
RAM CRC
Error Keys
Signal for Key “k”'
Reference for Key “k”
Status for Key “k”
Detect Output States
Last Command
Setups
Device ID
Firmware Version
Code
0xC0
0xC1
0xC2
0xC3
0xC4
0xC5
0x2k
0x4k
0x8k
0xC6
0xC7
0xC8
0xC9
0xCA
Note
Returns the first detected key
Returns all keys
Returns the device status
Returns the EEPROM CRC
Returns the RAM CRC
Returns the error keys
Returns the signal for key “k”
Returns the reference for key “k”
Returns error conditions/touch indication
Returns the detect output states
Returns the last command sent to QT1111
Returns the setup data
Returns the device ID
Returns the firmware version
Data Returned
1 byte
2-byte bitfield
1-byte bitfield
1 byte
1 byte
2-byte bitfield
2-byte number
2-byte number
1 byte
1 byte
1 byte
42 bytes
1 byte
1 byte
Note that SPI communications are full-duplex, so the host must transmit on the MOSI pin to keep the
communications active, while reading data from the QT1111 on the MOSI pin. Failure to do this within 100 ms will
cause the device to assume that the exchange has been abandoned and reset the SPI interface. The host should
therefore send one or two “NULL” bytes, as appropriate, on the MOSI line as it receives the 1- or 2-byte report data
from the device.
6.2 First Key (0xC0)
This command returns 1-byte report in the format shown in Table 6-2.
Table 6-2. Send First Key Report Format
Byte 0
Bit 7
DETECT
Bit 6
NUMKEY
Bit 5
ERROR
Bit 4
Bit 3
Bit 2
Bit 1
KEY_NUM
Bit 0
DETECT: 0 = no key in detect; 1 = there is a key in detect.
NUMKEY: indicates the number of keys in detect:
0 = only one key is in detect (specified by “KEY_NUM”)
1 = more than one key in detect.
AT42QT1111-MU / AT42QT1111-AU [DATASHEET]
23
9571C–AT42–05/2013