User manual
MGC3130 Hillstar Development Kit User’s Guide
DS40001721A-page 28 2013 Microchip Technology Inc.
The I
2
C to USB Bridge is powered via the USB port. Microchip’s Low Dropout (LDO)
Voltage Regulator MCP1801 is used to transform the 5V USB power to 3.3V required
for the PIC18F14K50. By default, 3.3V are also routed to the MGC3130 Unit via the I
2
C
interface. The 3.3V power supply towards the MGC3130 Unit can be cut by removing
the 0 resistor R7.
The LEDs indicate the following:
• POWER – signals that the I
2
C to USB Bridge is powered (3.3V)
• LED1 – blinks fast (~10 Hz) to indicate that there is no USB connection
established
• LED1 – blinks slow (~1 Hz) to indicate that the USB connection is established
• LED 2 – is on when there is data on the I
2
C bus
• LED 2 – is off when there is no data on the I
2
C bus
The communication between Bridge and MGC3130 Unit is accomplished via a 2-wire
I
2
C compatible serial port. Please refer to Figure 3-7.
In addition, the Hillstar Development Kit integrates an open-drain transfer status line
(TS) and the MGC3130 MCLR
signal, according to the MGC3130 reference circuitry.
TS is connected to the RC0 pin of the PIC18F14K50 and MCLR
to RC6.
For a detailed description of the I
2
C interface refer to the “MGC3130 Single-Zone 3D
Gesture Controller Data Sheet” (DS40001667).
The default I
2
C address of the bridge is set to 0x42 but can also be switched to 0x43
by changing the firmware running on the PIC18F14K50.
FIGURE 3-7: I
2
C™ AND USB DATA INTERFACE
For Schematics, Layout and Bill of Material of the I
2
C to USB Bridge please refer to
Appendix A.
Note: To update the PIC18F14K50 firmware, please refer to ‘MGC3130
PIC18F14K50 Host Reference Code’, available on
www.microchip.com/GestICGettingStarted.’
PIC18F14K50
RB4
RB6
RC0
RC6
RA0
RA1
SDA
SCL
TS
3.3V
1.8kΩ
10kΩ
1.8kΩ
MCLR
10kΩ
MGC3130
SI0
SI1
EIO0
MCLR
I
2
C
TM
to USB BridgeMGC3130 Unit
USB D+
USB D-
USB
I
2
C
TM
MasterI
2
C
TM
Slave
PC