GtDio6xChannelGetSenseLoadResistance

Applies To

GX5961, GX5964, File

Purpose

Returns the specified channel input pull-up and pull-down resistive loads.

Syntax

GtDio6xChannelGetSenseLoadResistance (nHandle, nChannel, pdPullUp, pdPullDown, pnStatus)

Parameters

Name
Type
Comments
nHandle
SHORT
Session identifier:

●     Board handle is used when communicating with the hardware. The Board handle session identifier is returned by calling GtDio6xInitialize or GtDio6xSetupInitialization.

●     File handle is used when communicating with a file. The File handle session identifier is  returned by calling GtDio6xFileOpen.
nChannel
SHORT
Used to specify the channel to Get. This parameter is 0-based and refers to any channel in the Domain. Auxiliary channel numbers begin with 1000.
GX5961: Each GX5961 board has 4 fully programmable auxiliary channels, and 8 TTL I/O channels. First 4 auxiliary channels may use all the Pin Electronics API.
GX5964: Does not have Auxiliary channels.
pdPullUp
PDOUBLE
Used to return the input load pull up resistance.
Input pull-up resistive loads can be one of the following:

●     GTDIO6X_RESISTIVE_LOAD_240_OHMS = 240.

●     GTDIO6X_RESISTIVE_LOAD_290_OHMS = 290.

●     GTDIO6X_RESISTIVE_LOAD_1K_OHMS = 1000.

●     GTDIO6X_RESISTIVE_LOAD_OPEN = -1.
pdPullDown
PDOUBLE
Used to return the input load pull down resistance.
Input pull down resistive loads can be one of the following:

●     GTDIO6X_RESISTIVE_LOAD_240_OHMS = 240.

●     GTDIO6X_RESISTIVE_LOAD_290_OHMS = 290.

●     GTDIO6X_RESISTIVE_LOAD_1K_OHMS = 1000.

●     GTDIO6X_RESISTIVE_LOAD_OPEN = -1.
pnStatus
PSHORT
Returned status: 0 on success, negative value on failure.

Comments

Each channel has an independent load with the following capabilities:

●     Channels’ Input constant source and sink currents up to 24 mA – GtDio6xSetSenseLoadCurrent function.

●     Maintain high impedance over a wide voltage.

●     Separate high and low commutating voltages – GtDio6xSetSensetLoadCommutatingVoltage function.

●     Channels’ Input Resistive load options - GtDio6xSetSenseLoadResistance function.

●     With independent high and low commutating voltages, the source and sink currents each have their own threshold voltage. If the voltage on the input, when the load is activated, is between the two commutating voltages, the load will remain in a high impedance state.

The input resistive load is useful in applications with very low DUT output swings (where a traditional active load will not switch on and off completely or quickly) and also as a means of forcing the DUT to a known voltage when the DUT is in HiZ..

Note: The source and sink currents should be programmed to 0 during normal operation of the resistive load.

When the resistive load is placed in HiZ (GTDIO6X_RESISTIVE_LOAD_OPEN) it maintains a low leakage current when the input voltage is between the supply rails.

Channels input pull-up and pull-down resistive loads can be read back and set dynamically at any time even while the DIO is running mode.

Example

The following example sets channel 0 and 2 sense load resistance to 240Ohms pull-up and 1K pull down, and return channel 0 settings:

 

DOUBLE dPullUp, dPullDown;

SHORT nStatus;

LONG alChannelList[2];

 

// Fill channel array

alChannelList[0] = 0;

alChannelList[1] = 2;

GtDio6xChannelSetSenseLoadResistance(nHandle, 2 alChannelList, GTDIO6X_RESISTIVE_LOAD_240_OHMS, GTDIO6X _RESISTIVE_LOAD_1K_OHMS, &nStatus);

 

GtDio6xChannelGetSenseLoadResistance(nHandle, 0, &dPullUp, &dPullDown, &nStatus);

 

See Also

GtDio6xChannelSetSenseLevels, GtDio6xChannelSetSenseLoadCommutatingVoltage, GtDio6xChannelSetSenseLoadCurrent, GtDio6xChannelSetSenseLoadResistance,  GtDio6xChannelSetSenseLoadState, GtDio6xGetErrorString