Tyco 1529L - Manual (Page 98)

USB IntelliHead Swipe Reader
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rate decreases the USB bus bandwidth used by the device. This property is
stored in non-volatile EEPROM memory so it will not change when the unit is
power cycled. The value of this property, if any, will be sent to the host when
the host requests the device’s USB endpoint descriptor. When this property is
changed, the unit must be power cycled to have these changes take effect for
the USB descriptor. If a value other than the default value is desired, it can be
set by the factory upon request. Examples follow:
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
MAX_PACKET_SIZE PROPERTY
Property ID:
3
Property Type: Byte
Length: 1 byte
Get Property: Yes
Set Property: Yes
Default Value: 8
Description: The value is a byte that represents the devices maximum packet size for
the Interrupt In Endpoint. The value can be set in the range of 1 – 64 and has units of bytes. The
maximum packet size tells the host the maximum size of the Interrupt In Endpoint packets. For
example, if the maximum packet size is set to 8, the device will send HID reports in multiple
packets of 8 bytes each or less for the last packet of the report. This property can be used to
speed up or slow down the time it takes to send card data to the host. Larger packet sizes speed
up communications and smaller packet sizes slow down communications. 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.
This property is stored in non-volatile EEPROM memory so it will not change when the unit is
power cycled. The value of this property will be sent to the host when the host requests the
device’s USB endpoint descriptor. When this property is changed, the unit must be power
cycled to have these changes take effect for the USB descriptor. If a value other than the default
value is desired, it can be set by the factory upon request. Examples follow:
Example Set MAX_PACKET_SIZE property Request (Hex):
Cmd Num Data Len Prp ID Prp Value