User's Manual

Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
Americas: [phone] Option 2
Europe: [phone]
Hong Kong: [phone]
www.lairdtech.com/wireless
10
CONN-GUIDE-BT740_v0.2
Signal Name
Pin No
I/O
Comments
UART_RX
22
I
UART_CTS
25
I
UART_RTS
24
O
UART_DSR
16
I
UART_DTR
29
O
Shared with GPIO3
UART_RI
28
I or O
Direction may be programmed.
UART_DCD
17
I or O
Direction may be programmed.
2.4.2.4 SPI Bus
Signal Name
Pin No
I/O
Comments
SPI_MOSI
2
I
INTERNAL USE ONLY - Used to reprogram Flash in Laird
production.
SPI_MISO
33
O
SPI_CSB
32
I
SPI_CLK
6
I
2.4.2.5 PCM Interface
Signal Name
Pin No
I/O
Comments
PCM_CLK
7
I or O
If unused, keep pins open.
PCM output signals are tri-stated when there is not an active
SCO or eSCO connection.
PCM_IN
9
I
PCM_SYNC
8
I or O
PCM_OUT
10
O
2.4.2.6 General Purpose I/O and ADC
Signal Name
Pin No
I/O
Signal level
Comments
GPIO_3 - 9
3, 4, 16,
17, 18,
19, 29,
30, 31
I or O
See Recommended
Operating Parameters
Analogue0, Analogue1
14, 21
I
Range 0 – 1.8 V
8 bit
2.4.2.7 Miscellaneous
Signal Name
Pin No
I/O
Signal level
Comments
USB D-
27
I
V
IL
max =0.3vdd_usb
V
IH
min =0.7vdd_usb
Normally inactive. Pull to GND
through 10 kΩ.
USB D+
26
I
V
IL
max =0.3vdd_usb
V
IH
min =0.7vdd_usb
Normally inactive. Pull to GND
through 10 kΩ.
RESET
5
I
V
IL
max=1.0V
V
IH
min=2.3V
Active LOW. The Reset input
contains a 10 kΩ pull-up resistor
(internal to module).
Terminology:
USB Signal Levels: vdd_usb refers to the internal voltage generated by the LDO regulator on the module,
typically 3.3 V. Hence 0.3vdd_usb and 0.7vdd_usb correspond to 1.0 V to 2.3 V. Achieving 3.3V for
vdd_usb requires VCC_IN of 3.5V. USB IO voltage levels follow VCC_3V3. Correct USB operation
requires vdd_usb on 3.1 V, which requires of VCC_IN of ~3.3V (0.2V LDO drop).