CYV15G0404RB

JTAG Support

The CYV15G0404RB contains a JTAG port to allow system level diagnosis of device interconnect. Of the available JTAG modes, boundary scan and bypass are supported. This capability is present only on the LVTTL inputs and outputs and the TRGCLKx± clock input. The high-speed serial inputs and outputs are not part of the JTAG test chain.

To ensure valid device operation after power-up (including non-JTAG operation), the JTAG state machine must also be initialized to a reset state. This must be done in addition to the device reset (using RESET). Initialize the JTAG state machine using TRST (assert it LOW and deassert it or leave it asserted), or by asserting TMS HIGH for at least 5 consecutive TCLK cycles. This is necessary in order to ensure that the

Table 5. Receive BIST Status Bits

JTAG controller does not enter any of the test modes after device power-up. In this JTAG reset state, the rest of the device will operate normally.

Note The order of device reset (using RESET) and JTAG initialization does not matter.

3-Level Select Inputs

Each 3-Level select input reports as two bits in the scan register. These bits report the LOW, MID, and HIGH state of the associated input as 00, 10, and 11 respectively

JTAG ID

The JTAG device ID for the CYV15G0404RB is ‘0C811069’x.

{BISTSTx, RXDx[0],

Description

Receive BIST Status

RXDx[1]}

 

(Receive BIST = Enabled)

000, 001

BIST Data Compare. Character compared correctly.

010

BIST Last Good. Last Character of BIST sequence detected and valid.

 

 

011

Reserved.

 

 

100

BIST Last Bad. Last Character of BIST sequence detected invalid.

101

BIST Start. Receive BIST is enabled on this channel, but character compares have not yet

 

commenced. This also indicates a PLL Out of Lock condition.

110

BIST Error. While comparing characters, a mismatch was found in one or more of the character bits.

 

 

111

BIST Wait. The receiver is comparing characters, but has not yet found the start of BIST character to

 

enable the LFSR.

Document #: 38-02102 Rev. *C

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Cypress CYV15G0404RB manual Jtag Support, Receive Bist Status Bits, Level Select Inputs