Compaq 99875320-5 manual Pollinginterval Property, Cmd Num Data Len Prp ID Prp Value

USB HID IntelliHead Swipe Reader

POLLING_INTERVAL PROPERTY

Property ID:	0x02
Property Type:	Byte
Length:	1 byte
Get Property:	Yes
Set Property:	Yes
Default Value:	10
Description:	The value is a byte that represents the devices polling interval for the Interrupt
	In Endpoint. The value can be set in the range of 1 – 255 and has units of
	milliseconds. The polling interval tells the host how often to poll the device
	for card data packets. For example, if the polling interval is set to 10, the host
	will poll the device for card data packets every 10ms. This property can be
	used to speed up or slow down the time it takes to send card data to the host.
	The trade-off is that speeding up the card data transfer rate increases the USB
	bus bandwidth used by the device, and slowing down the card data transfer
	rate decreases the USB bus bandwidth used by the device. The value of this
	property, if any, will be sent to the host when the host requests the device’s
	USB endpoint descriptor.
	This property is stored in non-volatile memory, so it will persist when the unit
	is power cycled. When this property is changed, the unit must be reset (see
	Command Number 2) or power cycled to have these changes take effect.

Example Set Polling Interval property Request (Hex):

Cmd Num	Data Len	Prp ID	Prp Value
01	02	02	0A

Example Set Polling Interval property Response (Hex):

Result Code	Data Len	Data
00	00

Example Get Polling Interval property Request (Hex):

Cmd Num	Data Len	Prp ID
00	01	02

Example Get Polling Interval property Response (Hex):

Result Code	Data Len	Prp Value
00	01	0A

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