CHAPTER 10 NB85E901
Preliminary User’s Manual A14874EJ3V0UM
246
10.5.2 Example of recommended circuit when connecting NB85E901 and NU85E
Figure 10-4 shows an example of the circuit recommended for IE connector section (target system side).
Figure 10-4. Example of Recommended Circuit for IE Connection (NU85E + NB85E901)
TRCDATA0
TRCDATA1
TRCDATA2
TRCDATA3
TRCEND
TRCCLK
A1
A2
A3
A4
A5
A6
DCK
DMS
DDI
DDO
DRSTZ
DBINT
DCK
DMS
DDI
DDO
DRSTZ
Note 1
A8
Note 2
A9
Note 2
A7
Note 2
A10
A11
4.7 k
Ω
+3.3 V
Note 3
22
Ω
50 k
Ω
External event
detection device, etc.
NU85E + NB85E901
IE connector
(target system side)
8830E-026-170S/L
V
DD
+3.3 V
B13
GND
B1 to B10
A12
A13
B11
B12
(Open)
(Open)
(Open)
(Open)
(Reserved)
(Reserved)
(Reserved)
(Reserved)
3 V buffer
Note 4
ASIC
Notes 1.
Make the clock pattern length as short as possible, and shield it by surrounding it with GND. Avoid
exceeding a pattern length of 100 mm.
2.
Make the pattern length as short as possible. Avoid exceeding a pattern length of 100 mm.
3.
Recommended buffer: SN74LVC541A (product of TI Corporation) or TC74LCX541F (product of
Toshiba Corporation)
4.
An output buffer with a drive capability of at least 6 mA is recommended.
Remarks 1.
The V
DD
pin (pin B13) of the IE connector (target system side) is only used to detect whether
power has been applied to the target system.
2.
The DBINT pin is optional. However, because the DBINT pin is necessary for testing, it must be
output off the chip as an external pin, even when not being used (the DBINT pin can be used as
the alternate function of a pin other than the test bus pins (TBI39 to TBI0, TBO34 to TBO0)).
When it is unnecessary to input a debug interrupt externally, input a low level to this pin.