Microchip Technology DM240312 Data Sheet
PIC24FJ256DA210 Development Board User’s Guide
DS51911A-page 40
2010 Microchip Technology Inc.
FIGURE 4-5:
UART CONFIGURATION
4.4.3.1
UART AND USB OTG MODE (TX REMAPPING)
Normally, the UART TX signal appears on pin RF3, along with the USBID signal. When
USB OTG mode is enabled, USBID takes priority over the TX signal. If the UART is also
needed, this requires the TX signal to be remapped to another pin. The development
board allows for RG8, normally used for S1/PAD1/LED1, to function as the TX signal
in these cases. In addition to remapping the pin in software using PPS, resistor R4, R5,
R26 and R27 will also need to be changed (Figure 4-6).
USB OTG mode is enabled, USBID takes priority over the TX signal. If the UART is also
needed, this requires the TX signal to be remapped to another pin. The development
board allows for RG8, normally used for S1/PAD1/LED1, to function as the TX signal
in these cases. In addition to remapping the pin in software using PPS, resistor R4, R5,
R26 and R27 will also need to be changed (Figure 4-6).
To remap the TX signal with USB OTG enabled:
1.
If populated, remove resistor R4 (callout 1). Alternatively, remove jumper JP13
(callout 2). (Both disconnect the TX signal from pin RF3.)
(callout 2). (Both disconnect the TX signal from pin RF3.)
2.
Populate resistor R5 (callout 1) with a
0
resistor (connects USBID signal to pin
RF3).
3.
Populate resistor R27 with a
0
resistor (callout 2) (connects TX signal to pin RG8).
4.
If populated, remove resistor R26 (callout 2) (disconnects Overcurrent Sense
signal).
signal).
FIGURE 4-6:
REMAPPING THE UART TX SIGNAL
M
M
1
2