Laird BL654PA, User Manual

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Note : The BL654PA UART signal levels always need to match the supply voltage net VDD_VSRC_nRF, of the
BL654PA.
Figure 11: USB to UART (via FTDI chip on dev board) interface via analog switch U15
J1 pinout is designed to be used with FTDI USB-UART TTL (3.3V) converter cables (found at
http://www.ftdichip.com/Products/Cables/USBTTLSerial.htm). One example is FTDI part TTL-232R-3V3.
If the BL654PA on the development board is powered from 1.8V supply, then you must use the 1.8V version of the FTDI USB-
UART cable. UART signal levels always need to match the supply voltage net VDD_nRF_SW of the BL654PA development
board.
Figure 12: J1 wiring to match FTDI USB-UART cable (TTL-232R-3V3 cable)
Fit a jumper in J35 (to switch the Analog switch U15 and route BL654PA UART to J1) when connecting an external FTDI USB-
UART TTL (3.3V) converter cable using J1.
Fitting a jumper in J35 also allows the BL654PA UART to be routed to Atmel MCU UART (signal also on J19 and net names
beginning with IMCU_) via open solder bridges SB16 to SB19 shown in
Figure 13 . You must connect these bridges with
solder. This may be useful for those customers wanting to work with the Nordic SDK.
IMCU_CTS
IMCU_RxD
C8
0.1uF,16V
GND
IMCU_RTS
IMCU_TxD
USB_CTS
Module_CTS
VDD_VSRC_nRF
R7
10K
R6 0R
R9 0R
R12 0R
R21 0R
USB_RX
R19
10K
PIN HEADER,2.54mm 1X2P
J35
1
1
2
2
USB_DETECT Pins connect
High 1A-->1B1,
2A-->2B1,
3A-->3B1,
4A-->4B1
Module_RX
GND
SIO_08
VDD_VSRC_nRF
SIO_05
SIO_06
SIO_07
VDD_VSRC_nRF
USB_TX
USB_RTS
VDD_VSRC_nRF
U15
Dual DPDT,1.65V~4.45V
1B0
1
1B1
15
2B0
5
2B1
3
1A
16
2A
4
1S
2
3B0
9
3B1
7
4B0
13
4B1
11
3A
8
4A
12
2S
10
GND
6
VCC
14
Module_RTS
Module_TX
R2
10K
GND
R3
10K R10
10K R11
10K
SIO_06
R1
NOPOP (0R)
Module pin BL654 UART Data Flow
SIO_06 Module_TX Output
SIO_08 Module_RX Input
SIO_05 Module_RTS Output
SIO_07 Module_CTS Input
SIO_07
SIO_08
VDD_VSRC_nRF
SIO_05
FTDI (USB to TTL 232 Cable)
GND
USB_CTS
VCC
USB_TX
USB_RX
USB_RTS GND
RTS
VCC
RX
TX
CTS
J1
NOPOP (PIN HEADER,2.54mm 1X6P)
1
1
2
2
3
3
4
4
5
5
6
6
GND
USB-UART
bridge chip
FTDI
FT232RQ
BL654PA
module
UART
BL654 UART J35
routed to FTDI: No Jumper in J35 (default).
routed to Atmel: Fit Jumper in J35.