AT42QT1111MU ATMEL [ATMEL Corporation], AT42QT1111MU Datasheet - Page 13

• Manufacturer Part Number: AT42QT1111MU
• Manufacturer: ATMEL [ATMEL Corporation]

4.1.5.1
9571A–AT42–02/10
Set Instructions
For example,
Keys” report. In this exchange, the host sends:
and the QT1110 returns (simultaneously):
If CRC is enabled, this exchange is extended to 5 bytes, as shown in
Figure 4-4.
Set Instructions are 2-byte transmissions by the host that are used to send settings to individual
locations in the device memory map.
At the first byte, the QT1111 returns 0x55 (“Idle”) to confirm that it will interpret the byte as a new
command. At the second byte, the QT1111 returns the “Set” command it has just received.
For example, to set the “Positive Recalibration Delay” to 1920 ms, address 5 in the memory map
is set to 12 (0x0C). This is done with the “Set” command for address 5 (command code 0x95),
as shown in
0xC1 — 0x00 — 0x00
0x55 — Report Byte 0 — Report Byte 1
Host (Sends on MOSI)
Figure 4-5 on page
Figure 4-3 on page 12
All Keys Report – CRC Enabled
Response: 0x94 (Expected Command CRC)
Response: 0x55 ( Idle”
AT42QT1111-MU/AT42QT1111-AU
14.
Key Status Report Byte 0
Key Status Report Byte 1
Command CRC: 0x94
shows the exchange that takes place to read the 2-byte “All
Report CRC: 0x??
Command: 0xC1
Null: 0x00
Null: 0x00
Null: 0x00
“
–
Fresh Command)
Device (Responds on MISO)
Figure
Simultaneous
Transmission
4-4.
13