peb20525 Infineon Technologies Corporation, peb20525 Datasheet - Page 250

• Manufacturer Part Number: peb20525
• Description: 2 Channel Serial Optimized Communication Controller For Hdlc/ppp
• Manufacturer: Infineon Technologies Corporation

Table 33
Instruction (Bit 2 … 0)
000
001
010
011
111
others
EXTEST is used to examine the interconnection of the devices on the board. In this test
mode at first all input pins capture the current level on the corresponding external
interconnection line, whereas all output pins are held at constant values (‘0’ or ‘1’,
according to
the same time the next scan vector is loaded from TDI. Subsequently all output pins are
updated according to the new boundary scan contents and all input pins again capture
the current external level afterwards, and so on.
INTEST supports internal testing of the chip, i.e. the output pins capture the current level
on the corresponding internal line whereas all input pins are held on constant values (‘0’
or ‘1’, according to
next test vector is serially loaded via TDI. Then all input pins are updated for the
following test cycle.
Note: In capture IR-state the code ‘001’ is automatically loaded into the instruction
SAMPLE/PRELOAD is a test mode which provides a snap-shot of pin levels during
normal operation.
IDCODE: A 32-bit identification register is serially read out via TDO. It contains the
version number (4 bits), the device code (16 bits) and the manufacturer code (11 bits).
The LSB is fixed to ‘1’.
TDI ->
Note: Since in test logic reset state the code ‘011’ is automatically loaded into the
BYPASS: A bit entering TDI is shifted to TDO after one TCK clock cycle.
Data Sheet
register, i.e. if INTEST is wanted the shift IR-state does not need to be passed.
instruction register, the ID code can easily be read out in shift DR state which is
reached by TMS = 0, 1, 0, 0.
Table
Boundary Scan Test Modes
0010
Table
32). Then the contents of the boundary scan is shifted to TDO. At
0000 0000 0101 1111
32). The resulting boundary scan vector is shifted to TDO. The
Test Mode
EXTEST (external testing)
INTEST (internal testing)
SAMPLE/PRELOAD (snap-shot testing)
IDCODE (reading ID code)
BYPASS (bypass operation)
handled like BYPASS
250
0000 1000 001
1 -> TDO
PEB 20525
PEF 20525
Test Modes
2000-09-14