Locus Engineering E1947 User manual

Locus Engineering Inc. E1947
3 Pin C2 Programming Adapter
FEATURES
adapts between Silicon LabsTM SB
Debug Adapter 10 pin IDC connector and
a 3 pin connector on the target board
reset switch
power good LED
program cable with 3 pin 2mm
connector
conformal coated and insulated
saves space on target PCB
DESCRIPTION
The E1947 3 Pin C2 Programming Adapter allows Silicon LabsT microcontroller
designs to use a small 3 pin connector for programming instead of the 10 pin IDC
interface from the USB Debug Adapter. All isolation circuitry for the C2 data and C2
clock is included, as well as a reset switch and USB power good LED. This simplifies
the target board to only a 3 pin programming connector for the C2 data, clock, and
ground. The interface includes a strain relieved programming cable with a 3 pin 2mm
machined contact male header connector. The module is insulated to protect against
unintentional minor electrical contact. Custom programming cables can be added at the
spare connector areas on the board.
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Electrical and Mechanical S ecifications E1947
Figure 1. Module Schematic
Figure 2. Module Dimensions
Name Description Connector Pad
C2D C2 Serial Data Square pa
GND Groun Mi le roun pa
C2K C2 Serial Clock Outsi e roun pa
Table 1. C2 Connector Descri tion
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USB 5V GOOD LED
SWITCH
RESET
0.500"
2.050"
GND
C2K
C2D
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E1947 C2 PROGRAM INTER ACE .

A lication Information E1947
Installation
Connect the Silicon LaboratoriesT USB Debug AdapterT IDC connector to the E1947
adapter. The green LED indicates when the USB 5V is on. Note that the USB 5Vis not
used to power the target board.
Connect the 3 pin 2mm connector from the E1947 adapter to the target board such that
the C2D and C2K signals go to the microcontrollers’ corresponding pins.
Open the Silicon Labs IDE program.
Power the target board.
Connect to the target board using the IDE program. Check that the Power and
Run/Stop LEDs on the USB Debug Adapter are both on.
If the IDE hangs up due to static events for example, unplug the USB cable, wait a
second, reconnect it, then reconnect to the target board using the IDE program.
If the C2D and C2K signals are reversed, the IDE will not connect but there will be no
damage. Simply reverse the connection and reconnect using the IDE program.
The reset switch can be used to reset the program on the microcontroller while it is
running.
Programming Cable O tions
The other 3 pin C2 connections on the E1947 board can be used for custom cables with
connectors other than 2mm pitch. All Locus Engineering micorcontroller development
boards include 2mm connectors with machined contacts compatible with the E1947
adapter and included cable. If other programming connectors are used, protect the
existing one from inadvertent electrical contact with heat shrink or tape.
Custom cables can be strain relieved with silicone sealant where the cable attaches to
the board.
Programming Connector O tions
For prototyping it is best to use mating connectors on the target board for
programming. In production however, the C2 connector on the target board is not
needed as only the through hole pads are sufficient. Simply place the E1947 adapter
cable connector into the C2 location on the target board and press the connector gently
on an angle to ensure contact while the programming takes place. Alternatively, a 3 pin
cable with spring loaded pogo pins can be used as well.
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A lication Information E1947
Figure 1. Exam le Setu of E1947 3 Pin C2 Programming Ada ter
General Precautions
Charged devices and circuit boards can discharge without warning. Proper ESD precautions should be
followed to avoid failure.
This device is not authorized for use in any product where the failure or malfunction of the product can
reasonably be expected to cause failure in a life support system or to significantly affect its operation.
Locus Engineering Inc. reserves the right to make changes at any time without notice to improve product
features or reliability.
Information is provided by Locus Engineering Inc. with the best of intentions without any warranty
expressed or implied. As such Locus Engineering Inc. disclaims all liabilities or responsibilities for any
use of the information, any inaccuracies or fitness for a particular purpose.
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