ht82k95ee Holtek Semiconductor Inc., ht82k95ee Datasheet - Page 20

• Manufacturer Part Number: ht82k95ee
• Description: Ht82k95ee/ht82k95ae -- Usb Multimedia Keyboard Encoder 8-bit Mcu
• Manufacturer: Holtek Semiconductor Inc.

Data EEPROM Timing Diagrams
Note:
Suspend Wake-Up and Remote Wake-Up
If there is no signal on the USB bus for over 3ms, the
HT82K95EE/HT82K95AE will go into suspend mode.
The Suspend line (bit 0 of the USC) will be set to 1 and
a USB interrupt is triggered to indicate that the
HT82K95EE/HT82K95AE should jump to the suspend
state to meet the 500 A USB suspend current spec.
In order to meet the 500 A suspend current, the firm-
ware should disable the USB clock by clearing the
USBCKEN (bit3 of the SCC) to 0 . The suspend cur-
rent is 400 A.
User can further decrease the suspend current to 250 A
by setting the SUSP2 (bit4 of the SCC). But if the
SUSP2 is set, user should make sure not to enable the
LVR OPT o p ti o n, othe rwi se the H T 82K9 5EE/
HT82K95AE will be reset.
When the resume signal is sent out by the host, the
HT82K95EE/HT82K95AE will wake-up the MCU by
USB interrupt and the Resume line (bit 3 of the USC) is
set. In order to make the HT82K95EE/HT82K95AE
function properly, the firmware must set the USBCKEN
(bit 3 of the SCC) to 1 and clear the SUSP2 (bit4 of the
SCC). Since the Resume signal will be cleared before
the Idle signal is sent out by the host, the Suspend line
(bit 0 of the USC) will be set to 0 . So when the MCU is
detecting the Suspend line (bit0 of USC), the Resume
line should be remembered and taken into consider-
ation.
After finishing the resume signal, the suspend line will
go inactive and a USB interrupt is triggered. The follow-
ing is the timing diagram.
Rev. 1.20
The write cycle time t
condition of sequential command.
WR
is the time from a valid stop condition of a write sequence to the end of the valid start
20
The device with remote wake up function can wake up
the USB Host by sending a wake-up pulse through
RMWK (bit 1 of the USC). Once the USB Host receives
a wake-up signal from the HT82K95EE/HT82K95AE, it
will send a Resume signal to the device. The timing is as
follows:
HT82K95EE/HT82K95AE
August 28, 2006