2.0 Programming Description

2.1 MICROWIRE INTERFACE

The 22-bit shift register is loaded via the MICROWIRE interface. The shift register consists of a 20-bit Data[19:0] Field and a 2-bit

Address[1:0] Field as shown below. The Address Field is used to decode the internal control register address. When LE

transitions HIGH, data stored in the shift register is loaded into one of 4 control registers depending on the state of the address

bits. The MSB of Data is loaded in first. The Data Field assignments are shown in Section 2.3 CONTROL REGISTER CONTENT

MAP.

MSB

LSB

Data[19:0]

Address[1:0]

21

2 1

0

2.2 CONTROL REGISTER LOCATION

The address bits Address[1:0] decode the internal register address. The table below shows how the address bits are mapped into

the target control register.

Address[1:0]

Target

Field

Register

0

0

RF2 R

0

1

RF2 N

1

0

RF1 R

1

1

RF1 N

2.3 CONTROL REGISTER CONTENT MAP

The control register content map describes how the bits within each control register are allocated to specific control functions.

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