Polling interval property, Track data send flags property – MagTek MICRSafe99875466 User Manual

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Section 5. USB Communications

POLLING INTERVAL PROPERTY

Property ID:

Property Type:

Byte

Length:

1 byte

Get Property:

Yes

Set Property:

Yes

Default Value:

Description:

The value is a byte that represents the device’s 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 keystroke data packets. For example, if the polling interval is set to
10, the host will poll the device for keystroke data packets every 10ms. This
property can be used to speed up or slow down the time it takes to send
keystroke 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 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 for these changes to take effect.

Example Set Polling Interval property Request (Hex):

Cmd Num

Data Len

Prp ID

Prp Value

Example Set Polling Interval property Response (Hex):

Result Code Data Len

Data

Example Get Polling Interval property Request (Hex):