GS3281 datasheet(33/97 Pages) SEMTECH

33 / 97 page

GS3281

Final Data Sheet

Rev.7

PDS-061453

January 2019

33 of 97

Semtech

Proprietary & Confidential

www.semtech.com

Matrix-Scan Procedure:

1. Set the bounds of the matrix-scan with the offset and step parameters described in

Table 4-5. The default value results in a full matrix-scan. Alternatively, the

shape-scan can be executed and the coordinates returned can be used to minimize

the scan time and data size of the scan.

2. Configure the 4-point error rate threshold by setting each of the parameters listed

in Table 4-6.

3. Configure the eye monitor to run a matrix-scan by setting

CTRL_EYE_SHAPE_SCAN_B to 0.

4. Start the scan and poll the scanner status register until the scan is complete. Please

refer to the flow diagram in Figure 4-10.



Read Eye Scan Buffer Procedure:

1. Host reads image size from STAT_EYE_IMAGE_SIZE.



Note: The matrix-scan is composed of multiple partial scan segments. The size (in

Bytes) of the last partial scan segment is stored in STAT_EYE_IMAGE_SIZE.

2. Host reads scan buffer data from register 0x6CC1 to (0x6CC1 + (size read from

STAT_EYE_IMAGE_SIZE)/2).

 Address 0x6CC1 is the first header word corresponding to the last vertical offset

position in the matrix that was read.

 Address 0x6CC2 is the second header word corresponding to the image size.

This value is a copy of the image size that was read from

STAT_EYE_IMAGE_SIZE.

 Address 0x6CC3 to (0x6CC1 + (size read from STAT_EYE_IMAGE_SIZE)/2) is the

eye scan data.

 The image data is 2 bytes per sample point.

 Making reference to the Matrix shown in Figure 4-6, the eye scan data

starting at 0x6CC3 is stored in order from left to right, top to bottom, from

the last stored vertical/horizontal position in the matrix.

The number of samples contained in the scan buffer is equal to (size read from

STAT_EYE_IMAGE_SIZE - 4)/2.

GS3281 Datasheet(PDF) 33 Page - Semtech Corporation