Stollmann BlueMod+S/AI Application guide

BlueMod+S/AI
Hardware Reference
Release r00d01

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Note
This device was developed for the purpose of communication in an office environment. It is
intended solely for our industrial clients for physical integration into their own technical products
after careful examination by experienced technical personnel for its suitability for the intended
purpose. The device was not developed for or intended for use in any specific customer
application. The firmware of the device may have to be adapted to the specific intended modalities
of use or even replaced by other firmware in order to ensure flawless function in the respective
areas of application. Performance data (range, power requirements, etc.) may depend on the
operating environment, the area of application, the configuration, and method of control, as well as
on other conditions of use; these may deviate from the technical specifications, the Design Guide
specifications, or other product documentation. The actual performance characteristics can be
determined only by measurements subsequent to integration. Variations in the performance data of
mass-produced devices may occur due to individual differences between such devices. Device
samples were tested in a reference environment for compliance with the legal requirements
applicable to the reference environment. No representation is made regarding the compliance with
legal, regulatory, or other requirements in other environments. No representation can be made and
no warranty can be assumed regarding the suitability of the device for a specific purpose as
defined by our customers. Stollmann reserves the right to make changes to the hardware or
firmware or to the specifications without prior notice or to replace the device with a successor
model. Of course, any changes to the hardware or firmware of any devices for which we have
entered into a supply agreement with our customers will be made only if, and only to the extent
that, such changes can reasonably be expected to be acceptable to our customers. No general
commitment will be made regarding periods of availability; these must be subject to individual
agreement. All agreements are subject to our Terms and Conditions for Deliveries and Payments,
a copy of which is available from Stollmann.
Copyright © 2013 Stollmann E+V GmbH
Trademarks
The Bluetooth®word mark and logos are owned by the Bluetooth SIG, Inc. and any use of such
marks by Stollmann E+V GmbH is under license. Other trademarks and trade names are those of
their respective owners.

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Table of contents
1Introduction..............................................................................................................................8
1.1 Feature Summary.............................................................................................................8
1.2 Applications ......................................................................................................................9
Support for any additional profile is possible on request...........................................................9
1.2.1 General Cable Replacement......................................................................................9
1.2.2 Industry......................................................................................................................9
1.2.3 POS/Advertising ........................................................................................................9
1.2.4 Healthcare and Medical.............................................................................................9
1.2.5 Sports and Fitness.....................................................................................................9
1.2.6 Entertainment............................................................................................................9
2Block Diagram .......................................................................................................................10
3Application Interface ..............................................................................................................11
3.1 Power Supply .................................................................................................................11
3.2 Power-up Slew-Rate.......................................................................................................11
3.3 Reset..............................................................................................................................12
3.4 Serial Interface................................................................................................................14
3.4.1 3-Wire Serial Interface.............................................................................................15
3.4.2 Baudrate Deviation..................................................................................................16
3.5 GPIO Interface................................................................................................................17
3.6 I2C Interface....................................................................................................................17
3.7 SPI Serial Peripheral Interface........................................................................................18
3.8 Bluetooth Radio Interface ...............................................................................................18
3.9 Slow Clock Interface.......................................................................................................19
3.9.1 SLCK Specification (External Supplied Signal) ........................................................19
3.9.2 32,768 kHz Crystal Oscillator Specification (32k XOSC)..........................................19
3.9.3 Connection of an External 32,768 kHz Crystal.........................................................20
3.10 Test Mode Enable...........................................................................................................20
3.11 Operating in a Power-Switched Environment..................................................................21
3.12 Serial Wire Interface .......................................................................................................21
4Module Pins...........................................................................................................................22
4.1 Pin Numbering................................................................................................................22

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4.2 Pin Description................................................................................................................23
4.2.1 General Pin Description...........................................................................................23
4.2.2 Application Specific Pin Description.........................................................................24
4.2.2.1 TIO Pin Configuration...........................................................................................24
4.3 Handling of Unused Signals............................................................................................25
5Electrical Characteristics........................................................................................................26
5.1 Absolute Maximum Ratings ............................................................................................26
5.2 Electrical Requirements..................................................................................................26
5.3 Operating Conditions......................................................................................................26
5.4 Environmental Requirements..........................................................................................27
5.5 DC Parameter.................................................................................................................27
5.5.1 General Purpose I/O (GPIO)....................................................................................27
5.5.2 EXT-RES#...............................................................................................................28
5.5.3 External Slow Clock SLCK.......................................................................................28
5.6 Power Consumption and Power Down Modes................................................................29
5.6.1 Terminal I/O Configuration.......................................................................................29
5.7 RF Performance .............................................................................................................31
5.7.1 BLE Receiver...........................................................................................................31
5.7.2 BLE Transmitter.......................................................................................................32
5.7.3 Antenna-Gain and Radiation Pattern .......................................................................34
5.8 Power-Up Time...............................................................................................................34
6Mechanical Characteristics....................................................................................................35
6.1 Dimensions.....................................................................................................................35
6.2 Recommended Land Pattern..........................................................................................35
6.3 Re-flow Temperature-Time Profile..................................................................................36
6.4 Placement Recommendation..........................................................................................37
6.5 Housing Guidelines.........................................................................................................37
6.6 Antenna Issues...............................................................................................................37
6.7 Safety Guidelines............................................................................................................38
7Application Diagram...............................................................................................................39
8Approvals/Certifications .........................................................................................................40
8.1 Declaration of Conformity CE..........................................................................................40

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8.2 FCC Compliance ............................................................................................................40
8.2.1 FCC Grant...............................................................................................................41
8.2.2 FCC Statement........................................................................................................42
8.2.3 FCC Caution............................................................................................................42
8.2.4 FCC Warning...........................................................................................................42
8.2.5 FCC RF-exposure Statement...................................................................................42
8.2.6 FCC Labeling Requirements for the End Product ....................................................43
8.3 IC Compliance................................................................................................................44
8.3.1 IC Grant...................................................................................................................44
8.3.2 IC Statement............................................................................................................44
8.3.3 IC Caution................................................................................................................44
8.3.4 IC RF-exposure Statement ......................................................................................45
8.3.5 IC Labeling Requirements for the End Product........................................................45
8.3.6 IC Label Information BlueMod+S.............................................................................45
8.4 Bluetooth Qualification....................................................................................................45
8.5 RoHS Declaration...........................................................................................................46
9Related Documents ...............................................................................................................47
10 Packing ...............................................................................................................................48
10.1 Tape...............................................................................................................................49
10.2 Reel................................................................................................................................49
10.3 Package Label................................................................................................................50
11 Ordering Information ...........................................................................................................51
11.1 Part Numbers..................................................................................................................51
11.2 Standard Packing Unit....................................................................................................51
11.3 Evaluation Kit..................................................................................................................51
12 History.................................................................................................................................51
List of Figures
Figure 1: BlueMod+S/AI Block Diagram........................................................................................10
Figure 2: BlueMod+S Example Power Supply with LDO...............................................................11
Figure 3: BlueMod+S Example Reset ...........................................................................................12
Figure 4: Serial Interface Signals..................................................................................................14

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Figure 5: BlueMod+S Example Serial Interface (RS-232) Supporting UICP..................................15
Figure 6: BlueMod+S Example Serial Interface (Mixed Signal Level)............................................16
Figure 7: BlueMod+S I2C Interface................................................................................................17
Figure 8: BlueMod+S SPI Interface (Example: Master Mode).......................................................18
Figure 9: BlueMod+S connection of external XTAL.......................................................................20
Figure 10: BlueMod+S Pin Numbering (Top View)........................................................................22
Figure 11: Typical Antenna Radiation Pattern at 2402MHz...........................................................34
Figure 12: Typical Antenna Radiation Pattern at 2441MHz...........................................................34
Figure 13: Typical Antenna Radiation Pattern at 2480MHz...........................................................34
Figure 14: BlueMod+S/AI Dimensions ..........................................................................................35
Figure 15: BlueMod+S Land Pattern.............................................................................................35
Figure 16: Soldering Temperature-Time Profile (For Reflow Soldering)........................................36
Figure 17: BlueMod+S/AI Placement Recommendation................................................................37
Figure 18: Typical Application Schematics....................................................................................39
List of Tables
Table 1: Power up Rise Time Requirements.................................................................................11
Table 2: Pin States during Reset...................................................................................................13
Table 3: Deviation of Baudrates....................................................................................................16
Table 4: 32,768kHz Crystal Oscillator...........................................................................................19
Table 5: General Pin Assignment..................................................................................................23
Table 6: Application Specific Pin Assignments, TIO......................................................................24
Table 7: Absolute Maximum Ratings.............................................................................................26
Table 8: Electrical Requirements ..................................................................................................26
Table 9: DC Operating Conditions ................................................................................................26
Table 10: Environmental Requirements........................................................................................27
Table 11: DC Characteristics, Digital IO........................................................................................27
Table 12: DC Characteristics, EXT-RES#.....................................................................................28
Table 13: DC Characteristics, SLCK.............................................................................................28
Table 14: Supply Current Sleep Modes, no Radio Activity ............................................................29

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Table 15: Supply Current BLE Terminal I/O Profile, Peripheral Device Role.................................30
Table 16: RF Performance BLE Receiver .....................................................................................31
Table 17: RF Performance BLE Transmitter .................................................................................33

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1 Introduction
This Hardware Reference documents how the BlueMod+S/AI can be integrated into customer
systems. It addresses hardware specifications of the BlueMod+S/AI and requirements of the
hardware environments for the BlueMod+S/AI.
Notation: The term BlueMod+S refers to the BlueMod+S/AI and is used as an abbreviation.
For detailed information about software interfaces refer to [5].
For the latest version of this document please check the following URL:
http://www.stollmann.de/en/support/downloads/bluetooth-adapter/bluemod-s.html
1.1 Feature Summary
•Bluetooth specification V4.0 compliant
•Supports Bluetooth low energy
•Fully qualified Bluetooth V4.0 Single Mode LE
•CE certified
•FCC and IC certified
•Nordic nRF51822 inside
•Fast Connection Setup
•RF output power -30 up to +3dBm
•RSSI
•High sensitivity design
•Supply voltage range 1,8V to 3,6V
•Internal crystal oscillator (16 MHz)
•LGA Surface Mount type. BlueMod+S: 17 x 10 x 2.6 mm3
•Pin compatible to Stollmann BlueMod+SR dual mode module
•Shielded to be compliant to FCC full modular approval
•Flexible Power Management
•128-bit AES encryption
•High-speed UART interface
•I2C Master
•SPI Master/Slave interface
•Low power comparator
•Real Time Counter
•Up to 19 digital IO’s for individual usage by embedded software
•Up to 6 anlog inputs for individual usage by embedded software
•8/9/10bit ADC
•Arm® CortexTM-M0 core for embedded profiles or application software
•Manufactured in conformance with RoHS2
•Operating temperature -25 ... +75 °C
•Weight: tbd. g

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1.2 Applications
The BlueMod+S is designed to be used in low power applications, like sensor devices. Some
typical applications are described in this chapter.
Supported profiles are:
LE:
•Terminal IO
•any GATT based LE-profile
Support for any additional profile is possible on request.
1.2.1 General Cable Replacement
In case there is no standardized application specific profile available the BlueMod+S offers
Stollmann’s Terminal I/O profile, which allows transparent data transfer over UART and supports
Secure Simple Pairing, making the pairing process easy and the connection secure. Terminal I/O
is available for iOS and Android as well as implemented in Stollmann’s dual mode module
BlueMod+SR.
1.2.2 Industry
BlueMod+S can be used to monitor and control motors, actuators, values and entire processes.
1.2.3 POS/Advertising
BlueMod+S supports iBeacon or similar applications.
1.2.4 Healthcare and Medical
Usage of Bluetooth is aimed mainly at devices that are used for monitoring vital data. Typical
devices are blood glucose meter, blood pressure cuffs and pulse ox meters. Bluetooth BR/EDR
and low energy were chosen by the Continua Health Alliance as transports for interoperable end to
end communication.
1.2.5 Sports and Fitness
In the sports and fitness segment the BlueMod+S is used in devices for positioning as well as
monitoring vital data. Typical devices in this market are heart rate monitors, body temperature
thermometers, pedometers, cadence meters, altimeter, positioning / GPS tracking and watches
displaying information from sensors.
1.2.6 Entertainment
Bluetooth technology is already used in a wide variety of devices in the entertainment sector,
namely set-top boxes / gaming consoles. BlueMod+S is especially suited for use in remote
controls, gaming controller and wireless mouse/keyboard applications.

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2 Block Diagram
nRF51822
VSUP
BlueMod+S/AI
Balun+
Filter
RESET
I2C
UART
SPI
1 2
up to 7
3
GND
3.0V
16MHz
opt. 32kHz
Serial Wire
(DEBUG)
onboard
antenna
2
GPIO
up to 19
Analog In
up to 6
Figure 1: BlueMod+S/AI Block Diagram

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3 Application Interface
3.1 Power Supply
BlueMod+S require a power supply with the following characteristics:
Typical: 3,0VDC, min.: 1,8VDC, max.: 3,6VDC, thereby delivering > 25 mA peak
BlueMod+S is designed to be powered from 3V coin cell batteries e.g. CR2032 directly, or any
other power source complying with the given requirements. For optimal performance a stable
supply is recommended.
BlueMod+S
XC6204B-3.3
E-6,F-6
VSUP
GND:
A-7,E-7,F-7,B-[5:8],
C-[5:8],D-8,E-8,F-8
10µ + 100n
1µ
VOUT
VSS
VIN
CE
5 1
3
2
+5VDC
Figure 2: BlueMod+S Example Power Supply with LDO
3.2 Power-up Slew-Rate
Parameter Min Max Unit
VSUP rise time rate
(1), (2)
0 60 ms
(1) 0V to 1,8V
(2) The on-chip power-on reset circuitry may not function properly for rise times outside the
specified interval
Table 1: Power up Rise Time Requirements

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3.3 Reset
BlueMod+S are equipped with circuitry for generating power-up reset from the supply voltage
VSUP, as well as brownout detection.
During power-up, reset is kept until the supply voltage VSUP has reached the minimal operating
voltage. VSUP risetime has to comply with Table 1 for power-up reset to function properly. A reset
is also generated when VSUP falls below the threshold of the brownout detector (1,6V .. 1,7V with
a hysteresis of about 30mV), and is released when VSUP rises above that threshold.
By holding pin B-1 (EXT-RES#) at ≤ VSUP*0,3V for tHOLDRESETNORMAL ≥0,2µs, an external reset (pin
reset) is generated. This pin has a fixed internal pull-up resistor (RPU = 11kΩ... 16kΩ). EXT-RES#
may be left open if not used.
Note:
The reset-functionality associated with pin EXT-RES# is shared with the serial wire debug
feature (refer to 3.12). Inside the BlueMod+S module, EXT-RES# is connected to SWDIO via a
150R resistor. During a debug session the external reset function is not available; asserting of
EXT-RES# to any level should be avoided.
BlueMod+S
E-6,F-6
VSUP
GND
+3V3
EXT-RES# B-1
Reset-Switch is optional
Please Note: EXT-RES# of BlueMod+Shas approx. 13k internal pullup.
1k
Reset signal is optional
Host MCU
GPIO
VDD
Figure 3: BlueMod+S Example Reset

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The following table shows the pin states of BlueMod+S during reset active.
Pin Name State: BlueMod+S
EXT-RES# Input with pull-up
(1)
XL-IN/SLCK Input floating (disconnected)
XL-OUT Input floating (disconnected)
UART-TXD Input floating (disconnected)
UART-RXD Input floating (disconnected)
UART-RTS# Input floating (disconnected) with pull-up resistor 470kΩ
(2)
UART-CTS# Input floating (disconnected)
IUR-OUT# Input floating (disconnected)
IUR-IN# Input floating (disconnected)
GPIO[0:14] Input floating (disconnected)
TESTMODE# Input floating (disconnected)
BOOT0 Input floating (disconnected)
SWDIO Input with pull-up
(1)
SWCLK Input with pull-down
(1)
(1) pull-up, pull-down: RPU, RPD is typ. 13kΩ(11kΩto 16kΩ)
(2) a discrete resistor is used
Table 2: Pin States during Reset
The pin states as indicated in Table 2 are kept until hardware initialization has started.

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3.4 Serial Interface
The serial interface of BlueMod+S is a high-speed UART interface supporting RTS/CTS flow
control and interface-up/down mechanism according to the UICP+ protocol (refer to [3] ). Electrical
interfacing is at CMOS levels (defined by VSUP; see chapter 5.5.1).
•Transmission speeds are 9600 – 921600 bps and 1Mbps (asynchronous)
•Character representation: 8 Bit, no parity, 1 stop bit (8N1)
•Hardware flow-control with RTS and CTS (active low)
Note: Transmission speed may be limited by firmware. See corresponding command reference
[5] for further information.
BlueMod+S
Host
UART-RXD
UART-TXD
UART-CTS#
UART-RTS#
IUR-IN#
IUR-OUT#
Figure 4: Serial Interface Signals
The basic serial interface (with RTS/CTS flow control) uses only four signal lines (UART-RXD,
UART-TXD, UART-CTS#, UART-RTS#). IUR-IN#, IUR-OUT# and GPIO[4] (see below) can be left
unconnected.
A substantially saving of power during idle phases can be achieved (see 5.6.1) when the UICP
protocol is used (refer to [3] ). This protocol should be implemented on the host side as well.
Signals IUR-IN# and IUR-OUT# should be connected to the host and may be mapped to DSR and
DTR, if an RS232-style (DTE-type) interface is used (see Figure 5).
When using the TIO firmware and applications, call control can be supported by GPIO[4]. Driving
GPIO[4] to logic High level during a data transfer phase will “hang up” the connection and
disconnect the Bluetooth link. This signal may be mapped to DSR, if an RS232-style (DTE-type)
interface is used. Please refer to [5] for a functional specification. GPIO[4] can be left unconnected
if this feature is not used.

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3.4.1 3-Wire Serial Interface
When using only GND and UART-RXD, UART-TXD serial lines, leave UART-RTS# and UART-
CTS# open.
Note: It is strongly recommended to use hardware flow control. Not using flow control can cause
a loss of data.
2
BlueMod+S
GND
MAX3241
14
+3V3
22
23
2
3
7
8
4
6
1
9
TXD
RXD
RTS#
CTS#
IUR-OUT#
IUR-IN#
TXD
RXD
RTS
CTS
DTR
DSR
DCD
RI
RS232
DSUB9 (male)
DTE style connector pinout
9
4
10
5
11
6
7
8
19
13
18
12
17
16
15
F-4
D-2
D-7
F-3
B-4
D-5
UART_TXD
UART_RXD
UART_RTS#
UART_CTS#
IUR-OUT#
IUR-IN#
SHDN#
EN#
100n
100n
28
24
1
+3V3
100n 100n 100n
26
3
27
25
V+
VCC
V -
GND
C2+
C2-
C1+
C1-
220R
220R
220R
220R
220R
220R
5
SigGND
can be left open
VSUP
+3V3
Figure 5: BlueMod+S Example Serial Interface (RS-232) Supporting UICP

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VDDIO
(+1.2V .. +3.6V)
BlueMod+S
GND
D-2
F-4
F-3
D-7
UART_RXD
UART_TXD
UART_CTS#
UART_RTS#
10µ+100n+1n
SN74AVC4T245
User Host System
VSUP
XC6204B-3.3
VOUT
VSS
VIN
CE 1µ
100k
100k
VCCB
1B1
1B2
2B1
2B2 2A2
2A1
1A2
1A1
VCCA
1DIR
1OE
2DIR
2OE
(GPIO, Out,
no pu/pd)
(GPIO, Out,
no pu/pd)
TXD
RTS#
RXD
CTS#
+5VDC
OE_DRV#
BT_ENABLE
VDD_HOST (+1.2 .. +3.6V)
+3V3_switched
Figure 6: BlueMod+S Example Serial Interface (Mixed Signal Level)
3.4.2 Baudrate Deviation
The following table shows the deviation in percent of the standard data rates. The deviation may
be caused by the inaccuracy of the crystal oscillator or granularity of the baud rate generator.
Data Rate (bits/s) Deviation (%)
9600
±1%
19200
38400
57600
115200
230400
460800
921600
1000000
Table 3: Deviation of Baudrates
Note: The total deviation of sender and receiver shall not exceed 2,5% to prevent loss of data.

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3.5 GPIO Interface
It is possible to use the programmable digital I/Os GPIO[0:14] on the BlueMod+S. Their behavior
has to be defined project specific in the firmware.
Unused GPIO pins shall be left unconnected to stay compatible. There may be functions assigned
to some in future versions of the firmware.
3.6 I2C Interface1
The I2C bus interface serves as an interface between the internal microcontroller and the serial I2C
bus. BlueMod+S is the master and controls all I2C bus specific sequencing, protocol and timing. It
supports standard (100kHz) and fast (400kHz) speed modes. The BlueMod+S as an I2C master
must be the only master of the I2C bus (no multimaster capability). Clock stretching is supported.
GPIO[1]/I2C-SDA and GPIO[0]/I2C-SCL can be used to form an I2C interface. It is required to
connect 4k7 pull-up resistors on I2C-SCL and I2C-SDA when this interface is used.
I2C-SCL
I2C-SDA
GPIO[0]/I2C-SCL
GPIO[1]/I2C-SDA
BlueMod+S
VSUP
Rpu
+3.3V
B-2
D-3
E-6,F-6 +3.3V
Rpu
+3.3V
4k7
4k7
Figure 7: BlueMod+S I2C Interface
1subject to firmware support, contact Stollmann for current status

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3.7 SPI Serial Peripheral Interface2
The serial peripheral interface (SPI) allows for full-duplex, synchronous, serial communication with
external devices. The interface can be configured as the master and then provides the
communication clock (SCK) to the external slave device(s), or as the slave. The SPI Interface
supports SPI-modes 0 through 3. Module pins are used as follows:
•GPIO[2]: SPI-MOSI
•GPIO[5]: SPI-MISO
•GPIO[8]: SPI-SCK
GPIO[8]/SPI-SCK
GPIO[2]/SPI-MOSI
BlueMod+S
E-2
SPI-Master
connected device
SPI-Slave
GPIO[5]/SPI-MISO
D-1
F-2
SCK, SPI_CLK
SDI, MOSI
SDO, MISO
typical signals:
Figure 8: BlueMod+S SPI Interface (Example: Master Mode)
3.8 Bluetooth Radio Interface
The BlueMod+S/AI presents an integrated ceramic antenna.
It is highly recommended that you follow the design rule given in the Stollmann Application Note on
Antenna design [4].
2subject to firmware support, contact Stollmann for current status

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3.9 Slow Clock Interface
Even though an external slow clock is not required for BLE operation, consumption of power during
power-down modes can be reduced by feeding the module with an optional 32,768 kHz slow clock
at pin XL-IN/SLCK, or connecting an XTAL (32,768kHz) and two capacitors C1, C2 at pins XL-IN
and XL-OUT.
3.9.1 SLCK Specification (External Supplied Signal)
•32,768 kHz +/-250ppm; duty cycle 30...70%.
•Signal may be a sine wave, a clipped sine wave, a square wave or a rail-to-rail digital
signal. The amplitude must be at least 200mVpp. DC offset is not an issue as long as the
input voltage is between VSS and VDD at all times.
•connect signal SLCK to XL-IN/SLCK (A6) and leave XL-OUT (A5) open
3.9.2 32,768 kHz Crystal Oscillator Specification (32k XOSC)
Symbol Item Condition Limit Unit
Min Typ Max
fNOM Crystal Frequency Tamb = 25°C 32,768 kHz
fTOL Frequency Tolerance for
BLE applications including temperature and aging (1) +/-250 ppm
CLLoad Capacitance 9 12,5 pF
C0 Shunt Capacitance 2 pF
RSEquivalent Series Resistor 50 80 kΩ
PDDrive Level 1 µW
Cpin Input Cap. on XL-IN and
XL-OUT 4 pF
(1) adjust crystal frequency by choosing correct value for C1, C2 (value depends on C
L
of crystal
and layout)
Table 4: 32,768kHz Crystal Oscillator
The module’s firmware will detect the presence of a slow clock during the boot process and switch
behavior appropriately.

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3.9.3 Connection of an External 32,768 kHz Crystal
Connect the 32,768 kHz crystal and two capacitors C1, C2 at pins A-6 (XL-IN/SLCK) and A-5 (XL-
OUT). The crystal has to comply with specifications given in Table 1. The exact value of C1 and C2
depends on the crystal and the stray capacitance of the layout. Select C1, C2 such that the slow
clock oscillator operates at the exact frequency at room temperature (25°C). The crystal and the
capacitors shall be located close to pins A-5, A-6. Avoid long signal traces.
CL= (C1+Cpin+Cs) * (C2+Cpin+Cs) / (C1+C2+2*Cpin+2*Cs)
Cpin: see Table 4
Cs: stray capacitance, depends on layout
Figure 9: BlueMod+S connection of external XTAL
3.10 Test Mode Enable
For homologation purposes the ability of testmode operation like "Direct two wire UART Testmode"
is mandatory. The Direct Test Mode (as defined by the Bluetooth SIG) and additional test functions
are part of the BlueMod+S TIO-Firmware. Please refer to [7] and [8].
To enter and use test modes or DTM, access to the following signals is required:
•BOOT0
•TESTMODE#
•UART-RXD
•UART-TXD
•UART-CTS#
•GND
These pins shall be routed to some test pads on an outer layer, but can be left open during normal
operation when not used.
Please note the UART is required for operation of test modes. During the homologation process,
UART-RXD and UART-TXD must be freely accessible and connected via some RS232 level shifter
to the test equipment (like R&S CBT), whereas UART-CTS# must be set "active" (continuous low-
level) to allow serial communication.
XL-IN/SLCK
BlueMod+S
A-6
SlowClock
XL-OUT
A-5
32,768kHz
CL: 9pF
C1
C2
C1, C2 ~ 12pF