W7020 Datasheet, PDF (13/36 Pages) List of Unclassifed Manufacturers – Bluetooth Radio Module

Preliminary Data Sheet
September 2000
Serial Interface (continued)
CDI
CLOCKIR
SHIFTIR
UPDATEIR
W7020 Bluetooth Radio Module
STATUS
INSTRUCTION SHIFT
REGISTER
CDO
SHADOW LATCHES
INSTRUCTION REGISTER OUTPUT
Figure 5. Instruction Register
The data register has a structure similar to the IR. The data width is 8 bits.
The bypass register consists of a single register bit and forms a scan path between CDI and CDO.
CAP State Diagram
The CAP state diagram is shown in Figure 6. Transitions from one state to another depend on the CMS input and
occur at the rising edge of the CLK. The CMS and CDI inputs should change value on the falling edge of CLK.
The CDO output changes on the negative edge of CLK.
An instruction register scan (IR-scan) period starts with a status information download (capture-IR). The status
inputs to the instruction register are user-defined observability inputs. However, the two least significant status
information bits are fixed to 01 during the capture-IR according to the standard. Afterward, the data can be
shifted out (shift-IR) at the same time serial data is shifted in, or directly updated to the parallel output (exit1-IR,
update-IR). It also is possible for the IR-scan period to be paused (pause-IR) before a new data shift. A data
register scan period is identical, but there are no restrictions on the data during capture-DR.
The control-logic-reset state can always be reached from any other state by allowing the CMS input to be high for
five clock cycles.
Lucent Technologies Inc.
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