Microchip Technology DM240312 Datenbogen

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Development Board Hardware
 2010 Microchip Technology Inc.
DS51911A-page 47
4.4.6.1
DAUGHTER BOARD-SPECIFIC HARDWARE MODIFICATIONS
Depending on the PICtail Plus Daughter Board to be used, hardware modification to 
the development board may be required. The modifications re-route different signals 
from the microcontroller, particularly EPMP signals, to different pins of the connector. 
All changes consist of placing 
0
 resistors in designated areas to enable the connec-
tions, or removing existing resistors in other places to disable existing connections. All 
of the resistors are located in a single group adjacent to the Flash memory area, shown 
in Figure 4-10. They are also shown as a single group in Figure A-6 of the development 
board schematic.
FIGURE 4-10:
LOCATION OF CONFIGURATION RESISTORS
For additional information on the configuration resistors, as well as specific modifica-
tions for particular daughter boards, please refer to Appendix B. “Modifications for 
PICtail Plus Daughter Boards”
.
4.4.7
Current Measurement
To provide additional information on developing hardware solutions, the development 
board includes current measurement points at three locations. These permit the current 
drawn by the different branches of the development board to be measured separately.
The measurement points are unpopulated jumpers at JP1, JP2 and JP3 (Figure 4-11, 
callouts 1,2 and 3, respectively). To measure current, cut the trace on the reverse side 
of the board that shorts the two vias for the jumper, then insert the current measuring 
device between the two vias.
JP3 can be used to measure the total current drawn by the board from the 9V power 
supply. JP1 can be used to measure the total current (at 3.3V) drawn by the microcon-
troller, and JP2 can be used to measure the total current drawn by the remaining 3.3V 
branch of the board. The current drawn by the 5V branch can be measured by subtract-
ing the sum of the currents of JP1 and JP2 from the total current measured at JP3.
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