Elo TouchSystems 1525L manual Serialnum Property, Pollinginterval Property

Section 4. USB Communications

SERIAL_NUM PROPERTY

Property ID:	1
Property Type:	String
Length:	0 – 15 bytes
Get Property:	Yes
Set Property:	Yes
Default Value:	The default value is no string with a length of zero.
Description:	The value is an ASCII string that represents the device’s serial number.

This string can be 0 – 15 bytes long. 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 USB string 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 SERIAL_NUM property Request (Hex):

Cmd Num	Data Len	Prp ID	Prp Value
01	04	01	31 32 33

Example Set SERIAL_NUM property Response (Hex):

Result Code	Data Len	Data
00	00

Example Get SERIAL_NUM property Request (Hex):

Cmd Num	Data Len	Prp ID
00	01	01

Example Get SERIAL_NUM property Response (Hex):

	Result Code	Data Len	Prp Value
	00	03	31 32 33
POLLING_INTERVAL PROPERTY
Property ID:	2
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. 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,

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