TrueSecureTM
GTM-5110Cxx Series
Embedded Fingerprint Module
Revision: V1.00
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July 10, 2014
GTM-5110Cxx Series
Embedded Fingerprint Module
Table of Contents
1 Features.................................................................................................................... 3
2 Applications ............................................................................................................ 3
4 Block Diagram.......................................................................................................... 4
5 General Description................................................................................................. 4
6 Pin Description........................................................................................................ 5
7 Electrical Specifications......................................................................................... 5
8 Other Specifications................................................................................................ 6
9 Functional Description............................................................................................ 6
Hardware Description............................................................................................................. 6
Communication Protocol......................................................................................................... 7
Universal Asynchronous Receiver/Transmitter – UART.................................................................... 7
Checksum Generation....................................................................................................................... 7
Packet Types..................................................................................................................................... 8
Command Listing............................................................................................................................... 9
Command Description Details......................................................................................................... 10
Error Codes..................................................................................................................................... 26
Capturing a Fingerprint Image.............................................................................................. 27
Identifying and Verifying a Fingerprint Image....................................................................... 27
10 Application Circuit............................................................................................... 28
11 Mechanical Specifications.................................................................................. 29
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Table of Contents
3 Selection Table......................................................................................................... 3
GTM-5110Cxx Series
Embedded Fingerprint Module
1
Features
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2
Applications
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3
Features
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Single chip fingerprint recognition module
Complete integrated algorithms for learn, login and erase functions
Advanced optical technology
High accuracy and high recognition speed
Ultra-thin optical sensor
1:1 verification and 1:N identification
Downloadable sensor fingerprint image
Fingerprint templates can be read/written to module
UART communication protocol for interfacing to external master MCU
Easy fingerprint recognition product integration
Notebook computer login
Household security products
Vehicle entry systems
Biometric identification products
Selection Table
The range of devices shown in the selection table are similar in function, but differ mainly in their
fingerprint storage capacity, mechanical construction, pixel count, rotation range etc.
Part No.
Rev. 1.00
Effective Resolution
Area (mm2)
(DPI)
Image
Pixels
No. of
Fingerprints
Rotation
(Degree)
Template
Byte Size
Compare
Time - sec
GTM-5110C2R
14 × 12.5
450
240 × 216 20
±30
506
1.5
GTM-5110C3
14 × 12.5
450
258 × 202 200
360
498
1
GTM-5110C31
14 × 12.5
450
258 × 202 200
360
498
1
GTM-5110C5
14 × 12.5
450
258 × 202 2000
360
498
1.5
GTM-5110C51
14 × 12.5
450
258 × 202 2000
360
498
1.5
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GTM-5110Cxx Series
Embedded Fingerprint Module
4
Block Diagram
The following shows a simplified version of the internal functions of the fingerprint module.
Holtek
HT32F2755
ARM M3 Core
TX pin
RX pin
UART
Interface
Fingerprint
Recognition
Algorithm
5
General Description
Fingerprint recognition technology provides a secure and accurate means of biometric
identification. This range of device from offers users a quick and easy implementation method for
biometric fingerprint recognition. The integration of an optical fingerprint sensor, Holtek 32-bit
ARM core microcontroller and fully programmed algorithm into a single module together combine
to form complete fingerprint recognition module. A number of fingerprint images or templates
are stored within the devices internal Flash Memory and therefore retain storage when power is
removed. The storage capacity varies according to the module type selected. With easy commands
such as learn, login and erase, this range of device offer a convenient and easy to use solution for
users wishing to implement fingerprint biometric security into their products.
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Block Diagram
Fingerprint
Sensor
GTM-5110Cxx Series
Embedded Fingerprint Module
6
Pin Description
The fingerprint modules have a very simple 4 pin structure with two pins for power and the
remaining two for the UART communication.
Pin No.
1
TX
UART transmit pin
2
RX
UART receive pin
3
GND
Ground pin
4
VCC
Power Supply
Electrical Specifications
Symbol
Rev. 1.00
Function
Pin Description
7
Pin Name
Parameter
Test Conditions
Min
Typ
Max
Units
—
3.3
5.0
6.0
V
—
—
130
mA
—
—
0.8
V
0.8 VDD
—
—
V
—
0.4
V
VDD
Operating Voltage
IDD
Operating Current
VIL
RX input low voltage
—
VIH
RX input high voltage
—
VOL
TX input low voltage
IOL = TBD
—
VOH
TX input high voltage
IOH = TBD
2.9
—
—
V
IOL
TX port sink current
—
8
TBD
TBD
mA
tSST
System start up time
—
500
—
—
ms
RRVDD
VDD rise rate
—
TBD
—
—
V/ms
BRPON
Power-on Baud Rate
—
TBD
9600
TBD
Hz
No output pin load
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Embedded Fingerprint Module
8
Other Specifications
Item
Communication Interface
UART
Matching Mode
1:1, 1:N
False Acceptance Rate – FAR
< 0.001%
False Rejection Rate – FRR
< 0.1%
Enrollment time
< 3 sec (3 fingerprints)
Operating Environment Temp
-20°C ~ +60°C
Operating Environment Humidity
-20% ~ 80%
Storage Environment Temp
-20°C ~ +60°C
Storage Environment Humidity
10% ~ 80%
Other Specifications
9
Value
Functional Description
These fingerprint recognition modules, by integrating a fingerprint sensor, 32-bit Holtek
microcontroller and complete algorithms contain all the necessary hardware and software for full
implementation of fingerprint recognition functions. The user has only to communicate with the
fingerprint module using its UART interface to communicate with the internal hardware and to
implement functions such as learn, erase and login.
This set of devices communicates to the outside world via its internal UART interface. This would
normally be communication with an external UART interface equipped microcontroller.
Hardware Description
It is through an internal UART interface that the fingerprint module communicates with external
microcontrollers. There are two pins associated with the UART, one for data transmission, the TX
pin, and one for data reception, the RX pin. Both TX and RX pins have CMOS structures.
At power on the internal hardware will require a specific amount of time to initialise before
commands can be received over its UART interface from external hardware. This time is specified
in the electrical specifications. No command can be issued to the fingerprint module during this
period. Note also that a specific minimum power supply rise time is also required to ensure a
proper power on and initialise sequence.
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GTM-5110Cxx Series
Embedded Fingerprint Module
Communication Protocol
The fingerprint modules communicate with external hardware such as microcontrollers using a
fully internal UART interface. UART, means Universally Asynchronous Receiver Transmitter, and
is a very popular and easy to use communication method.
Universal Asynchronous Receiver/Transmitter – UART
Using this UART interface, an external microcontroller can communicate with the fingerprint
module by sending a fixed range of commands transmitted in packets. Within each UART frame
the data is preceded by a zero start bit and terminated by a high stop bit. There is no parity bit in
the UART frame.
Low Start Bit
0
High Stop Bit
D1
D0
D2
D3
D4
D5
D6
D7
1
8 Data Bits
UART Frame – 10 Bits
The fingerprint module UART interface contains its own internal Baud Rate generator. When the
device is first powered on this Baud Rate will be set to a default value of 9600 Hz. as specified
in the electrical characteristics. This Baud Rate can be changed to a different value using an
externally requested command sent over the UART interface to match the communication rate of
the master MCU. As the data communication is asynchronous the transmitter and receiver do not
share a common clock.
Checksum Generation
For each transmission, whether it be command, acknowledge or data, at the end of each data
packet, a checksum is generated. This is calculated by a simple addition of all the transmitted bytes
as follows:
Checksum = OFFSET[0]+…+OFFSET[4+N-1]
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Functional Description
It is through the UART interface that the fingerprint module communicates with external hardware.
There are two pins associated with the UART, one for data transmission, the TX pin, and one for
data reception, the RX pin. The UART interface sends a byte serially over time, with an indication
of start and end of a byte, in the form of start and stop bits, at a particular speed setup by the Baud
Rate. After power on the Baud Rate will default to a fixed value but can be later modified using a
UART command.
GTM-5110Cxx Series
Embedded Fingerprint Module
Packet Types
There are three packet types which are command, acknowledge and data. Multiple-bytes are
ordered using Little Endian. This is to say that the least significant bytes are stored in the lowest
addresses.
Offset
Content
Size
Description
0x55
BYTE
Command start code1
1
0xAA
BYTE
Command start code2
2
Device ID
WORD
Device ID: default is 0x0001, always fixed
4
Parameter
DWORD
Input parameter
8
Command
WORD
Command code
10
Check Sum
WORD
Check Sum (byte addition)
OFFSET[0]+…+OFFSET[9]=Check Sum
Functional Description
0
Command Packet Description
Offset
Content
Size
Description
0
0x55
BYTE
Response start code1
1
0xAA
BYTE
Response start code2
2
Device ID
WORD
Device ID: default is 0x0001, always fixed
4
Parameter
DWORD
Response == 0x30: (ACK) Output Parameter
Response == 0x31: (NACK) Error code
8
Response
WORD
0x30: Acknowledge (ACK).
0x31: Non-acknowledge (NACK).
10
Check Sum
WORD
Check Sum (byte addition)
OFFSET[0]+…+OFFSET[9]=Check Sum
Acknowledge Packet Description
Offset
Content
Size
Description
0
0x5A
BYTE
Data start code1
1
0xA5
BYTE
Data start code2
2
Device ID
WORD
Device ID: default is 0x0001, always fixed
4
Data
N BYTES
N bytes Data
The size is pre-defined per protocol stage
4+N
Check Sum
WORD
Check Sum (byte addition)
OFFSET[0]+…+OFFSET[4+N-1]=Check Sum
Data Packet Description
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GTM-5110Cxx Series
Embedded Fingerprint Module
Command Listing
All communication between external hardware, which in most cases will be a microcontroller, and
the fingerprint module is executed via the UART interface using a fixed set of commands. The full
set of commands along with their details are set out in the following chapters.
The following table provides a summary of all available commands.
Number HEX
Description
Functional Description
Rev. 1.00
Alias
01
Open
Initialisation
02
Close
Termination
03
UsbInternalCheck
Check if the connected USB device is valid
04
ChangeBaudrate
Change UART baud rate
05
SetIAPMode
Enter IAP Mode
In this mode, FW Upgrade is available
12
CmosLed
Control CMOS LED
20
GetEnrollCount
Get enrolled fingerprint count
21
CheckEnrolled
Check whether the specified ID is already enrolled
22
EnrollStart
Start an enrollment
23
Enroll1
Make 1st template for an enrollment
24
Enroll2
Make 2nd template for an enrollment
25
Enroll3
Make 3rd template for an enrollment, merge three templates
into one template, save merged template to the database
26
IsPressFinger
Check if a finger is placed on the sensor
40
DeleteID
Delete the fingerprint with the specified ID
41
DeleteAll
Delete all fingerprints from the database
50
Verify
1:1 Verification of the capture fingerprint image with the
specified ID
51
Identify
1:N Identification of the capture fingerprint image with the
database
52
VerifyTemplate
1:1 Verification of a fingerprint template with the specified
ID
53
IdentifyTemplate
1:N Identification of a fingerprint template with the
database
60
CaptureFinger
Capture a fingerprint image(256x256) from the sensor
61
MakeTemplate
Make template for transmission
62
GetImage
Download the captured fingerprint image(256x256)
63
GetRawImage
Capture & Download raw fingerprint image(320x240)
70
GetTemplate
Download the template of the specified ID
71
SetTemplate
Upload the template of the specified ID
72
GetDatabaseStart
Start database download – obsolete
73
GetDatabaseEnd
End database download, – obsolete
80
UpgradeFirmware
Firmware Upgrade
81
UpgradeISOCDImage Not supported
30
Ack
Acknowledge.
31
Nack
Non-acknowledge.
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Embedded Fingerprint Module
Command Description Details
All of the GTM fingerprint modules share a common set of commands. However within a subset of
commands there are certain parameters that must also be transmitted., such as fingerprint ID and
certain data for that particular module. The value of these parameters differ according to specific
part numbers. The following table shows this command subset and the relevant parameters that
need to be defined within these commands.
GTM Device
Parameter
Type
5110C2R
5110C3/C31
5110C5/C51
CheckEnrolled
ID
0~19
0~199
0~1999
EnrollStart
ID
0~19
0~199
0~1999
DeleteID
ID
0~19
0~199
0~1999
Verify
ID
0~19
0~199
0~1999
ID
0~19
0~199
0~1999
Data
506
498
498
Data
506
498
498
VerifyTemplate
IdentifyTemplate
MakeTemplate
Data
506
498
498
GetImage
Data
240×216
258×202
258×202
GetRawImage
Data
240×216
160×120
160×120
ID
0~19
0~199
0~1999
Data
506
498
498
ID
0~19
0~199
0~1999
Data
506
498
498
GetTemplate
SetTemplate
The following describes each command in detail.
Initialization (Open)
The Open command is used for module initialization and to obtain the module static information.
Field
Sample
Description
FirmwareVersion
FirmwareVersion: 20120225
Firmware version
IsoAreaMaxSize
IsoAreaMaxSize: 0KB
Maximum ISO CD image size
DeviceSerialNumber DeviceSN: EF15EF4016C66250-888F1A41
Unique device serial number
Description of devinfo structure
If the Module’s Serial Number is zero, it must be noted that the device may not operate correctly.
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Functional Description
Command Name
GTM-5110Cxx Series
Embedded Fingerprint Module
Host
Device
Host Command Packet
Command = Open
Parameter =
Zero: no request for extra information
Nonzero: requires extra information
If the host requests extra information then provide
the following:
Module Data Packet
Data =
typedefstruct_devinfo
{
DWORD FirmwareVersion;
DWORD IsoAreaMaxSize;
BYTEDeviceSerialNumber[16];
} devinfo;
Termination (Close)
The Close command results in no action.
Host
Device
Host Command Packet
Command = Close
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Module Response Packet
Response = Ack
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Functional Description
Module Response Packet
Response = Ack
GTM-5110Cxx Series
Embedded Fingerprint Module
Fast device search (UsbInternalCheck)
Operation is similar to a removable CD drive. However if there is another removable CD in the
system, it may take a longer time to achieve a connection. The UsbInternalCheck command is used
to overcome this problem by fast searching for the device.
Host
Device
Functional Description
Host Command Packet
Command = UsbInternalCheck
Module Response Packet
Response = Ack
Parameter = 0x55
CMOS LED control (CmosLed)
The CMOS (Sensor) LED default condition is an OFF condition. However, note that during the
boot process, the LED will flash once, providing an indication that the LED is working. So it is
important to send an LED ON command before any data capture actions are executed.
Host
Device
Host Command Packet
Command = CmosLed
Parameter =
Zero: Off LED
Nonzero: On LED
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Module Response Packet
Response = Ack
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GTM-5110Cxx Series
Embedded Fingerprint Module
Changing the UART baud rate (ChangeBaudrate)
The UART baud rate can be changed using this command during normal running. After power on
the module will be initialised to a 9600 bps UART baud rate.
Host
Device
Functional Description
Host Command Packet
Command = ChangeBaudrate
Parameter = baud rate (9600~115200)
Module Response Packet
Response = Ack:
Response = Nack: Error
NACK_INVALID_PARAM
Obtain enrolled fingerprint count (GetEnrollCount)
Host
Device
Host Command Packet
Command = GetEnrollCount
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Module Response Packet
Response = Ack
Parameter = Enrolled Fingerprint Count
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GTM-5110Cxx Series
Embedded Fingerprint Module
Check enrollment status (CheckEnrolled)
Host
Device
Host Command Packet
Command = CheckEnrolled
Parameter = ID(0~1999)
Functional Description
Module Response Packet
Response = Ack: This ID is enrolled
Response = Nack: Error
NACK_INVALID_POS
NACK_IS_NOT_USED
Start an enrollment process (EnrollStart)
Host
Device
Host Command Packet
Command = EnrollStart
Parameter = ID(0~1999)
If ID == -1, then “Enrollment without
saving” will be stated.
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Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_DB_IS_FULL
NACK_INVALID_POS
NACK_IS_ALREADY_USED
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GTM-5110Cxx Series
Embedded Fingerprint Module
Generate the first enrollment template (Enroll1)
Host
Device
Host Command Packet
Command = Enroll1
Functional Description
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_ENROLL_FAILED
NACK_BAD_FINGER
Duplicated ID(0~1999)
Generate the second enrollment template (Enroll2)
Host
Device
Host Command Packet
Command = Enroll2
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_ENROLL_FAILED
NACK_BAD_FINGER
Duplicated ID(0~1999)
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GTM-5110Cxx Series
Embedded Fingerprint Module
Generate the third enrollment template and then merge the three templates (Enroll3)
To implement a full fingerprint enrollment process, the host must send out the previous four
commands. More details regarding this is provided in a different section.
Host
Device
Functional Description
Host Command Packet
Command = Enroll3
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_ENROLL_FAILED
NACK_BAD_FINGER
Duplicated ID(0~1999)
It should be noted that if EnrollStart was called
with ID = -1, this will result in the enrolled template
not being saved. Here it will be transferred to the
host, as shown below.
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Module Response Packet
Data = enrolled template (498 bytes)
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GTM-5110Cxx Series
Embedded Fingerprint Module
Check the finger press status (IsPressFinger)
During the enrollment process, this command is used during the time when the host is waiting for
the finger to be removed.
Host
Device
Module Response Packet
Response = Ack:
Parameter = Zero: finger is pressed
Parameter = nonzero: finger is not pressed
Delete a single fingerprint (DeleteID)
Host
Device
Host Command Packet
Command = DeleteID
Parameter = ID(0~1999)
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Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_INVALID_POS
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Functional Description
Host Command Packet
Command = IsPressFinger
GTM-5110Cxx Series
Embedded Fingerprint Module
Delete all fingerprints (DeleteAll)
Host
Device
Host Command Packet
Command = DeleteAll
Functional Description
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_DB_IS_EMPTY
1:1 Verification (Verify)
Host
Device
Host Command Packet
Command = Verify
Parameter = ID(0~1999)
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Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_INVALID_POS
NACK_IS_NOT_USED
NACK_VERIFY_FAILED
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GTM-5110Cxx Series
Embedded Fingerprint Module
1:N Identification (Identify)
Host
Device
Host Command Packet
Command = Identify
Functional Description
Module Response Packet
Response = Ack: OK
Parameter = 0~1999: identified ID
Response = Nack: Error
NACK_DB_IS_EMPTY
NACK_IDENTIFY_FAILED
1:1 Template Verification (VerifyTemplate)
Host
Device
Host Command Packet
Command = VerifyTemplate
Parameter = ID(0~1999)
Host Command Packet
Data = a template (498 bytes)
Rev. 1.00
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_INVALID_POS
NACK_IS_NOT_USED
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Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_COMM_ERR
NACK_VERIFY_FAILED
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GTM-5110Cxx Series
Embedded Fingerprint Module
1:N Template Identification (IdentifyTemplate)
Host
Device
Host Command Packet
Command = IdentifyTemplate
Host Command Packet
Data = a template (498 bytes)
Rev. 1.00
Functional Description
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_DB_IS_EMPTY
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Module Response Packet
Response = Ack: OK
Parameter = 0~1999: identified ID
Response = Nack: Error
NACK_COMM_ERR
NACK_IDENTIFY_FAILED
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GTM-5110Cxx Series
Embedded Fingerprint Module
Capture fingerprint (CaptureFinger)
The raw fingerprint image data is captured from the sensor using this command. As the fingerprint
algorithm is setup to process a 450dpi 256×256 image, the captured image is converted to a
256×256 image before algorithmic processing. If no finger is detected then the command will
return a non-acknowledge.
Host
Device
Functional Description
Host Command Packet
Command = CaptureFinger
Parameter =
Zero: not best image, but fast
Nonzero: best image, but slow
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_FINGER_IS_NOT_PRESSED
Generate a Template (MakeTemplate)
This command is used to generate a template for transmission. Before sending this command a
CaptureFinger command should have been previously sent. The template should not be used for
registration.
Host
Device
Host Command Packet
Command = MakeTemplate
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Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_BAD_FINGER
Module Response Packet
Data = made template (498 bytes)
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GTM-5110Cxx Series
Embedded Fingerprint Module
Obtain fingerprint image (GetImage)
Host
Device
Host Command Packet
Command = GetImage
Functional Description
Module Response Packet
Response = Ack: OK
Module Response Packet
Data = 258×202 image (52116 bytes)
Obtain raw image (GetRawImage)
Host
Device
Host Command Packet
Command = GetRawImage
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Capture raw image
Module Response Packet
Response = Ack: OK
Module Response Packet
Data = 160×120 QVGA image (19200 bytes)
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GTM-5110Cxx Series
Embedded Fingerprint Module
Obtain template (GetTemplate)
Host
Device
Host Command Packet
Command = GetTemplate
Parameter = ID(0~1999)
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Functional Description
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_INVALID_POS
NACK_IS_NOT_USED
Module Response Packet
Data = a template (498 bytes)
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GTM-5110Cxx Series
Embedded Fingerprint Module
Set template (SetTemplate)
Host
Device
Host Command Packet
Command = SetTemplate
Parameter = ID(0~1999)
(If Parameter’s HIWORD is non-zero,
fingerprint duplication check will not be
performed.)
Host Command Packet
Data = a template (498 bytes)
Functional Description
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_INVALID_POS
Module Response Packet
Response = Ack: OK
Response = Nack: Error
NACK_COMM_ERR
NACK_DEV_ERR
Duplicated ID(0~1999)
Start a database download – obsolete command (GetDatabaseStart)
This command is now obsolete, no longer required and therefore results in no action. It was
formerly used for RS232 interface communication purposes and for historical reasons remains.
Host
Device
Host Command Packet
Command = GetDatabaseStart
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Module Response Packet
Response = Ack
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GTM-5110Cxx Series
Embedded Fingerprint Module
End database download – obsolete command (GetDatabaseEnd)
This command is now obsolete, no longer required and therefore results in no action. It was
formerly used for RS232 interface communication purposes and for historical reasons remains.
Host
Device
Functional Description
Host Command Packet
Command = GetDatabaseEnd
Module Response Packet
Response = Ack
Upgrade Firmware (UpgradeFirmware)
Not supported
Upgrade the ISO CD Image (UpgradeISOCDImage)
Not supported
Set IAP Mode (SetIAPMode)
This command is used to make the module enter into the IAP Mode. When in the IAP mode a FW
upgrade can be executed.
Host
Device
Host Command Packet
Command = SetIAPMode
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Module Response Packet
Response = Ack
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GTM-5110Cxx Series
Embedded Fingerprint Module
Error Codes
When the response to any command is a Non-acknowledge, then an error code will be generated as
shown in the accompanying table.
NACK Parameter
Description
NACK_TIMEOUT
0x1001
Obsolete, capture timeout
NACK_INVALID_BAUDRATE
0x1002
Obsolete, Invalid serial baud rate
NACK_INVALID_POS
0x1003
The specified ID is not between 0~19
NACK_IS_NOT_USED
0x1004
The specified ID is not used
NACK_IS_ALREADY_USED
0x1005
The specified ID is already used
NACK_COMM_ERR
0x1006
Communication Error
NACK_VERIFY_FAILED
0x1007
1:1 Verification Failure
NACK_IDENTIFY_FAILED
0x1008
1:N Identification Failure
NACK_DB_IS_FULL
0x1009
The database is full
NACK_DB_IS_EMPTY
0x100A
The database is empty
NACK_TURN_ERR
0x100B
Obsolete, Invalid order of the enrollment
(The order was not as: EnrollStart → Enroll1 →
Enroll2 → Enroll3)
NACK_BAD_FINGER
0x100C
Too bad fingerprint
NACK_ENROLL_FAILED
0x100D
Enrollment Failure
NACK_IS_NOT_SUPPORTED
0x100E
The specified command is not supported
NACK_DEV_ERR
0x100F
Device Error, especially if Crypto-Chip is
trouble
NACK_CAPTURE_CANCELED
0x1010
Obsolete, The capturing is canceled
NACK_INVALID_PARAM
0x1011
Invalid parameter
NACK_FINGER_IS_NOT_PRESSED
0x1012
Finger is not pressed
Duplicated ID
0 – 19
There is duplicated fingerprint (while enrollment
or setting template), This error describes just
duplicated ID
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Functional Description
Rev. 1.00
Value
GTM-5110Cxx Series
Embedded Fingerprint Module
Capturing a Fingerprint Image
A fingerprint image can be read and stored by transmitting a series of commands to the fingerprint
module as follows.
IsPressFinger is used to check whether a finger has been placed on the sensor. This function is used
during enrollment.
GetRawImage is used to capture a raw live image. It will not check if a finger has been placed on
the sensor. This function is used for debug or calibration.
Identifying and Verifying a Fingerprint Image
After capturing a fingerprint image it then has to be identified and verified as follows.
Identify and IdentifyTemplate perform a 1: N matching operation.
Verify and VerifyTemplate perform a 1: 1 matching operation.
Before the image-related matching functions, Identify and Verify, are called, the host must first call
CaptureFinger.
Rev. 1.00
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Functional Description
CaptureFinger is used to capture the fingerprint image. If a finger has not been placed on the
sensor, it will return an error. If the function is successful, the device’s internal RAM will store the
data as a valid fingerprint image, ready for use by subsequent commands. If the host issues other
command, the fingerprint image will be used and destroyed.
GTM-5110Cxx Series
Embedded Fingerprint Module
10
Application Circuit
As the GTM series of Fingerprint Modules are fully integrated requiring no external components
for their operation, the addition of an external MCU, communicating via the UART interface is all
that is required to implement a fingerprint recognition system.
GTM-5110Cxx
Fringerprint Mod��e
Application Circuit
VDD
TX
Master MCU
RX
VSS
Rev. 1.00
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July 10, 2014
GTM-5110Cxx Series
Embedded Fingerprint Module
12.90
17
16.68
Mechanical Specifications
6.82
0.10
Pin1 = TX
Pin2 = RX
Pin3 = GND
Pin4 = VCC 3.3V~6V
6
2.16
16.90
5
21.13
37
0.75
1.46
9.27
3.70
July 10, 2014
29 of 30
Rev. 1.00
Mechanical Specifications
11
GTM-5110Cxx Series
Embedded Fingerprint Module
Mechanical Specifications
Copyright© 2014 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time
of publication. However, Holtek assumes no responsibility arising from the use of
the specifications described. The applications mentioned herein are used solely for
the purpose of illustration and Holtek makes no warranty or representation that such
applications will be suitable without further modification, nor recommends the use of
its products for application that may present a risk to human life due to malfunction or
otherwise. Holtek's products are not authorized for use as critical components in life
support devices or systems. Holtek reserves the right to alter its products without prior
notification. For the most up-to-date information, please visit our web site at http://www.
holtek.com.tw.
Note that Holtek’s fingerprint recognition products have been designed in conjunction with
Gingy Technology.
Rev. 1.00
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