Keyboard

Example

The following reports are sent if a user presses the Suspend/Sleep (Power Key 0) key on the key- board.

The Suspend/Sleep down key packet sent from the keyboard to the bridge is shown in Table 4-14.

Table 4-14. Example Suspend/Sleep Down Key Power Keys Report

Application Report

Application Report

Power Key Scan

Header

 

0xFE

0x02

The up key packet sent from the keyboard to the bridge is shown in Example Up Key Power Keys Report.

Table 4-15. Example Up Key Power Keys Report

Application Report

Application Report Header

0xFE

4.3.9.1.4Keep Alive Report

An Application Report Header of 0xFC indicates that this report is a Keep Alive report. Example of a Keep Alive reports sent from the keyboard to the bridge is shown in Table 4-16.

Table 4-16. Example Keep Alive Report (Null Packet Support disabled)

Application Report

Application Report Header

0xFC

If the bridge does not receive a Keep Alive packet or an up key within a specified interval (DOWNKEY_TIME_OUT) while a down key is present, the bridge generates an up key to the com- puter.

4.3.9.1.5Battery Voltage Level Report

An Application Report Header of 0xFD indicates that this report is a Battery Voltage Level report. The Battery Voltage Level report format is shown in Table 4-17.

Table 4-17. Battery Voltage Level Report Format

Byte

Name

2

Application Report Header

0xFD

 

3

Battery Voltage Level

The Battery Voltage Level ranges from 1 (low) to 10 (full).

The Battery Voltage Level report is sent after a keystroke that occurs whenever the keyboard has been in idle for more than 8 seconds.

CY4672 Reference Design Guide, Document # 001-16968 Revision **

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Cypress CY4672 manual Power Key Scan