Cypress OSM-2400 User manual

Page 1
Upgraded OSDP-
Wiegand Converter!
OSM-2400
Product Manual
Cypress Integration Solutions 35+ Years of Access Control Ingenuity CypressIntegration.com
©2022 Cypress Computer Systems 1778 Imlay City Road, Lapeer, MI 48446 800-807-2977
OSM-2400_Manual_221208

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Specifications
Part Number
Part Number
OSM-2400
UPC
816684006128
Physical
Physical Dimensions (L x W x H)
4.03 x 1.50 x 0.45 inches | 10.24 x 3.81 x 1.14 cm
Weight
1 oz. | 28.35 grams
Environmental
Operating Temperature Range
-40ºF to 158ºF | -40ºC to 70ºC
Enclosure Rating
No Enclosure, not rated for water or dust intrusion
Electrical
Supply Voltage
8 - 16 VDC (12 VDC Typical) @ 250 mA Max
Relay
Max Switching
220Vdc 30W (resistive) 1A / 250Vac 37.5VA 1A
Running Spec with load
30Vdc 1A (resistive) / 125 Vac 0.3A (resistive), 1x105
operations @ 20˚C
Additional
Features
Connect OSDP reader to Wiegand panel, or connect Wiegand reader to OSDP panel.
Supports Secure Channel Protocol for encrypted communication.
Supports firmware update with OSDP File Transfer.
Supports Wiegand readers and controllers with one or two LED control lines.
Use DIP switches to select OSDP device addresses 0-7. Device addresses 0-126 supported.
Supported baud rates: 9600, 19200, 38400, 57600, 115200, 230400.
Relay Output for tamper/supervision (ACU Mode) or general output (PD Mode).
Power inputs available on both headers, with passthrough (only use one at any given time).
Cypress OSM-2400 Manual - Product Overview & Specifications
The OSM-2400 is an upgraded replacement for the OSM-1000 Wiegand-OSDP converter. The
OSM-2400 is used to connect an OSDP reader to a Wiegand controller, or used to connect a
Wiegand reader to an OSDP controller. This allows users to begin adopting OSDP and gaining the
benefits, such as encrypted communication, without having to replace the entire system. The
OSM-2400 supports LED, Buzzer, and Relay Output I/O. DIP switches provide options for manually
setting the device address, selecting different modes for I/O behavior, and selecting different
modes for I/O behavior, and selecting the ACU or PD operating modes. !
It is recommended to maximize the OSDP run between the reader and the controller to provide the
most secure connection. When connecting an OSDP reader to a Wiegand controller, it is best to
install the OSM-2400 near the Wiegand controller. When connecting a Wiegand reader to an OSDP
controller, it is best to install the OSM-2400 near the Wiegand reader.
Related Products (sold separately)
OTT-2100
Pocket-sized OSDP COMSET Tool
Configure device address and baud rate without knowing current
settings, and can be used to default the SCBK.

Page 3
Cypress OSM-2400 Manual - Table of Contents
Table of Contents
Topic
Page
Overview and Specifications
2
OSDP Terminology
4
Using ACU Mode or PD Mode
5
Physical Features & Dimensions
6
Pin Designations
7
Power Input
8
ACU Mode Wiring Diagram
9
PD Mode Wiring Diagram
10
General OSDP Communication Information
11
PD Capability Report (PD CAP)
12-13
Status LED
14
DIP Switches
15-17
LED Modes
18-19
Using Secure Channel Communication
20-22
ACU Mode I/O Overview
23-24
ACU Mode LED Commands - Red LED Input
25
ACU Mode LED Commands - Green LED Input
26
ACU Mode LED Commands - Amber LED Input
27
ACU Mode LED Commands - OFF LED Input
28
ACU Mode LED Commands - Buzzer Input
29
PD Mode I/O Overview
30-31
PD Mode I/O - Wiegand Output
32
Firmware Upload Using File Transfer
33

Page 4
Cypress OSM-2400 Manual - OSDP Terminology
This section lists and defines in general terms OSDP terminology used in this manual. !
Access Control Unit (ACU): Typically the access controller, the ACU is the device on the OSDP
bus that controls the PDs. The ACU only sends commands to the PDs and waits for replies. !
Peripheral Device (PD): Typically a reader, but many other devices can be PDs, any device on the
OSDP bus that is not the ACU. PDs receive commands from the ACU and send replies. !
Device Address: OSDP Peripheral Devices are assigned an address, all PDs on the OSDP bus
must have a unique address. This address is used in commands from the ACU and in replies from
the PD to indicate which device the message is being sent to/from. !
Baud Rate: Data transfer rate, expressed in bits per second. Communication speed between ACU
and PD(s).!
Secure Channel Base Key (SCBK): 16 byte key set by the user used to initiate Secure Channel
communication sessions. !
Secure Channel Base Key Default (SCBK-D): Default SCBK value. Default value set by the
manufacturer or the default value defined in the OSDP specification.!
Secure Channel Session: OSDP communication sessions using the Secure Channel Protocol,
which, among other things, encrypts the data payload in OSDP messages. !
Unencrypted Communication Session: OSDP communication sessions without data payload
encryption. !
File Transfer: OSDP protocol used to transfer a file from the ACU to the PD. In the case of the
OSM-2400, a firmware file. !
NAK: Negative acknowledge reply from the PD. Indicates the PD had an error processing the
previous command or is incapable of processing the previous command. !
ACK: Positive acknowledge reply from the PD. The PD properly processed the previous command
or nothing to report to ACU. !
RAW: PD reply with card data payload. Card data is a raw string of bits. !
Manufacturer Specific Command: OSDP Command implemented by the manufacturer for special
device functions not found in the OSDP spec.

Page 5
Cypress OSM-2400 Manual - Using ACU Mode or PD Mode
ACU Mode (Access Control Unit)
ACU Mode is used to connect an OSDP reader to a Wiegand access controller. The OSM-2400 is
in ACU Mode when DIP switch 8 is ON. Application: Install OSDP readers in a legacy Wiegand
access system and enable Secure Channel encryption to protect high security areas.!
The OSM-2400 controls the OSDP reader. Credential data read by the OSDP reader is sent to the
OSM-2400 over the OSDP connection, then the OSM-2400 sends the credential data to the
Wiegand port over the Wiegand data lines. The I/O lines (LED and Buzzer) on the OSM-2400 are
connected to the Wiegand port. When the Wiegand access controller changes the state of the I/O
lines, the OSM-2400 translates the state of the I/O lines into OSDP commands that are sent to the
OSDP reader. !
The OSM-2400 supports one OSDP reader. The device address and baud rate must be the same
between the OSM-2400 and OSDP reader for proper OSDP communication be be achieved. The
OSM-2400 device address is set by DIP switches 1-3 or by the osdp_COMSET command (while in
PD Mode). The baud rate is set by the osdp_COMSET command (while in PD Mode).!
PD Mode (Peripheral Device)
PD Mode is used to connect a Wiegand reader to an OSDP access controller. The OSM-2400 is in
PD Mode when DIP switch 8 is OFF. Application: Support legacy Wiegand readers on an OSDP
access control system.!
The OSM-2400 is controlled by the OSDP access controller. Credential data read by the Wiegand
reader is sent to the OSM-2400 over the Wiegand data lines, then the OSM-2400 sends the
credential data to the OSDP access controller over the OSDP connection. The OSDP access
controller sends the OSM-2400 OSDP I/O commands (LED, Buzzer, and Relay Output). The
OSM-2400 controls the Wiegand reader by changing the state of its physical I/O according to the
OSDP commands.!
The OSM-2400 can be one of multiple PDs on the OSDP bus. The OSM-2400 will need to have a
unique device address (set with DIP switches 1-3 or by the osdp_COMSET command) and the
baud rate will need to match the baud rate of the OSDP access controller.

Page 6
Cypress OSM-2400 Manual - Physical Features & Dimensions
DIP Switches
Status LED
OSDP / Relay !
Header
Wiegand / !
I/O Header
4.03 inches (overall)
1.90 inches
(mounting holes)
1.50 inches
(overall)
1.30 inches
(mounting
holes)
Ø 0.125 inches x4

Page 7
Cypress OSM-2400 Manual - Pin Designations
8 - 16 VDC Input
Ground
Red LED Output
Green LED Output
Buzzer Output
Ground
Data 0 Input
Data 1 Input
RS-485 B+
RS-485 A-
Ground
Strike N.O.
Strike COM
Strike N.C.
Ground
8 - 16 VDC Input
PD Mode Pin Designations
8 - 16 VDC Input
Ground
Data 0 Output
Data 1 Output
Buzzer Input
Ground
Red LED Input
Green LED Input
RS-485 B+
RS-485 A-
Ground
Strike N.O.
Strike COM
Strike N.C.
Ground
8 - 16 VDC Input
ACU Mode Pin Designations

Page 8
Cypress OSM-2400 Manual - Power Input
The OSM-2400 is powered with 8 to 16 VDC (12 VDC typical) for the power input, and draws at
most 250 mA of current. There are two power inputs that are connected together (common), shown
in green text in the diagram below. The OSM-2400 can be powered by either power input, but not
both. Power can be passed through the OSM-2400 because the power inputs are common. Other
devices can be powered with the power input not connected to the power supply, provided power
supply can provide enough power for all devices. !
The four Ground pins (two on each header) are all common.!
IMPORTANT: DO NOT power the OSM-2400 with multiple power supplies. Doing so can cause
damage to the OSM-2400 and/or the power supplies.
8 - 16 VDC Input
Ground
Data 0 Output
Data 1 Output
Buzzer Input
Ground
Red LED Input
Green LED Input
RS-485 B+
RS-485 A-
Ground
Strike N.O.
Strike COM
Strike N.C.
Ground
8 - 16 VDC Input

Page 9
Cypress OSM-2400 Manual - ACU Mode Wiring Diagram
This wiring diagram shows the OSM-2400 in Single LED Mode (DIP Switch 4 ON) connecting to a Wiegand access controller with a single LED output.! If the Wiegand access controller being used has two LED outputs then the OSM-2400 should be used in Dual LED Mode (DIP Switch 4 OFF). The two LED outputs should be connected to the Red LED Input and Green LED Input on the OSM-2400.
Wiegand
Access
Control Panel
Ground
Data 0 Data 1
LED Out
Beeper Out
DC Power
Supply
Power
Ground
OSDP
Reader
OSM-2400
8 - 16 VDC Input Ground Data 0 Output Data 1 Output Buzzer Input Ground Red LED Input Green LED Input
RS-485 B+
RS-485 A-
Ground
Strike N.O.
Strike COM
Strike N.C.
8 - 16 VDC Input
Ground

Page 10
Cypress OSM-2400 Manual - PD Mode Wiring Diagram
This wiring diagram shows the OSM-2400 in Single LED Mode (DIP Switch 4 ON) connecting to a Wiegand reader with a single LED control line.! If the Wiegand reader being used has two LED control lines then the OSM-2400 should used in Dual LED Mode (DIP Switch 4 OFF). The two LED control lines should be connected to the Red LED Output and Green LED Output on the OSM-2400.
8 - 16 VDC Input Ground Red LED Output Green LED Output Buzzer Output Ground Data 0 Input Data 1 Input
RS-485 B+
RS-485 A-
Ground
Strike N.O.
Strike COM
Strike N.C.
8 - 16 VDC Input
Ground
RS485 A RS485 B
OSDP Access
Control Panel
DC Power
Supply
Power
Ground
Wiegand
Reader
OSM-2400

Page 11
Cypress OSM-2400 Manual - General OSDP Communication Information
Supported Device Addresses
The OSM-2400 supports device addresses 0-126. Device addresses 0-7 can be set using DIP
switches 1-3. In ACU Mode (Access Control Unit), the OSM-2400 device address is the address
the OSM-2400 will use to poll the OSDP reader or PD. In PD Mode (Peripheral Device), the device
address is the address the OSM-2400 will respond to the ACU on.!
Supported Baud Rates
The OSM-2400 supports 6 communication baud rates: 9600, 19200, 38400, 57600, 115200, and
230400. The communication baud rate is set by sending the osdp_COMSET command to the
OSM-2400 in PD Mode. The OSM-2400 default baud rate is 9600.!
Message Timeout
The message timeout is 200 milliseconds, as defined in the OSDP specification.!
In ACU Mode, the OSM-2400 will resend the command if it does not receive a reply from the OSDP
reader or PD within 200ms. !
Session Timeout
The OSDP session timeout is 8 seconds, as defined in the OSDP specification.!
In ACU Mode, if the OSM-2400 does not receive a reply from the PD within 8 seconds it will end
the OSDP communication session. A new OSDP communication session will be established in
order for communication to resume. !
In PD Mode, if the OSM-2400 does not receive a command from the ACU within 8 seconds it will
end the OSDP communication session. A new OSDP communication session needs to be
established in order for communication to resume.

Page 12
Cypress OSM-2400 Manual - Device Capabilities Report (PDCAP)
ACU Mode (Access Control Unit)
The OSM-2400 in ACU Mode does not send the osdp_CAP command to the connected OSDP
reader or PD to read its capabilities. The OSM-2400 will send the PD any control and I/O
commands based on the state of the DIP switches and inputs controlled by the Wiegand access
controller. If the OSDP reader or PD does not support the I/O command sent by the OSM-2400 it
should reply with a NAK. !
PD Mode (Peripheral Device)
The ACU can command the PD (OSM-2400) to provide a list of its device capacities, this is called
the Device Capabilities Report, or PDCAP. The PDCAP includes information about supported
credential formats/length, supported I/O, communication security, and more. The ACU sends the
osdp_CAP command and the PD replies with the osdp_PDCAP reply. !
The osdp_PDCAP reply data field contains the information about the device’s capabilities. The data
field is made up of multiple 3 byte sections for each capability. Each 3 byte section has three, one
byte fields; Function Code, Compliance, and Number Of. !
The OSM-2400 (PD Mode) osdp_PDCAP reply data field is below in HEX (Dual LED Mode):!
02 03 01 03 01 00 04 03 01 05 02 01 08 01 00 09 01 01 0A A0 05 0B 00 80 10 02 00!
The data field contains 10, 3 byte capability sections (30 bytes total). The table below and the table
on the following page break down these 3 byte capability sections by field and explain the meaning
of each.
Field Value
Meaning
Function Code: 02
Output Control
Compliance: 03
Output Supports Timed Control
Number of: 01
Device has 1 Output
Function Code: 03
Card Data Format
Compliance: 01
Device Supports RAW Replies up to 1024 Bits
Number of: 00
N/A
Function Code: 04
LED Control (Single LED Mode)
Compliance: 03
Bi-Color LED with Timed Control
Number of: 01
Device has 1 LED

Page 13
Cypress OSM-2400 Manual - PD Capability Report (PD CAP) (Cont.)
Field Value
Meaning
Function Code: 04
LED Control (Dual LED Mode)
Compliance: 04
Tri-Color LED with Timed Control
Number of: 01
Device has 1 LED
Function Code: 05
Audio Output
Compliance: 02
Audio Output Supports Timed Control
Number of: 01
Device has 1 Audio Output (Buzzer Output)
Function Code: 08
Check Character Support
Compliance: 01
CRC-16 is Supported
Number of: 00
N/A
Function Code: 09
Communication Security
Compliance: 01
AES128
Number of: 01
Device Uses OSDP Default Key
Function Code: 0A
Maximum Single Message Size (for File Transfer Protocol)
Compliance: A0
The size capabilities are calculated by adding the values in the
Compliance and Number Of fields. Device supports a maximum receive
buffer size of 1440 bytes.
Number of: 05
Function Code: 0B
Maximum Multi-Part Message Size (for File Transfer Protocol)
Compliance: 00
The size capabilities are calculated by adding the values in the
Compliance and Number Of fields. Device supports a maximum file size
of 32kB.
Number of: 80
Function Code: 10
OSDP Specification Compliance
Compliance: 02
Device Supports OSDP Version 2.2
Number of: 00
N/A

Page 14
Cypress OSM-2400 Manual - Status LED
The OSM-2400 has a single tri-color LED that displays Red, Green, Blue, and White to indicate the
state of the OSDP communication session. !
ACU Mode Status LED States:
Flashing RED: Attempting to poll PD with selected address!
Flashing BLUE: Unencrypted communication session with PD!
Flashing GREEN: Secure Channel communication session with PD!
Single WHITE Flash: Card or keypad data received from OSDP card reader and Wiegand Data
output to access controller!
PD Mode Status LED States:
Solid RED: No communication from ACU!
Flashing RED: The OSM-2400 detects valid OSDP communication on the bus, but the OSM-2400
is not being polled by the ACU!
Flashing BLUE: Unencrypted communication session with ACU!
Flashing GREEN: Secure Channel communication session with ACU!
Single WHITE Flash: Card or keypad data received from Wiegand card reader and RAW reply sent
to ACU!

Page 15
Cypress OSM-2400 Manual - DIP Switches
ON C & K ON
OFF
PD Address
or ACU
Polling Address
Enable Beep on Read
in ACU Mode
Require Secure
Channel
Invert LED I/O
Pin State
ACU or PD
Mode Select
LED Mode
Select

Page 16
Cypress OSM-2400 Manual - DIP Switches (Cont.)
DIP Switches 1-3 - Selecting PD Address or ACU Polling Address:
DIP Switches 1-3 are used to set the OSDP address of the OSM-2400 in PD Mode (Peripheral
Device), and to set the OSDP address the OSM-2400 will poll in ACU Mode (Access Control Unit).
Addresses 0-7 are able to be selected using the DIP Switches, see the table below. !
Other addresses can be set by sending the OSM-2400 the osdp_COMSET command while in PD
Mode. DIP Switches 1-3 need to all be OFF for the new address to be used. When DIP switches
1-3 are OFF, the OSM-2400 will check if any address has been set by the osdp_COMSET
command. If an address has ben set by the osdp_COMSET command that address will be used. If
no address has been set by the osdp_COMSET command, address 0 will be used. When DIP
Switches 1-3 are set to any address 1-7, those addresses will override any address set by the
osdp_COMSET command. !
Below is a table showing how DIP switches 1-3 are set to select the address.
X = ON
DIP Switch 4 - LED Mode Select:
DIP Switch 4 is used to select the LED mode. When DIP Switch 4 is OFF, the OSM-2400 is in Dual
LED Mode, for use with Wiegand readers or controllers with 2 LED lines. In Dual LED Mode both
the Red and Green LED lines are enabled and there are 4 possible LED states; RED, GREEN,
AMBER, and OFF. !
When DIP Switch 4 is ON, the OSM-2400 is in Single LED Mode, for use with Wiegand readers or
controllers with a single LED line. In Single LED Mode the Red LED line is enabled and the Green
LED line is disabled. When the Red LED line in in the normal state the LED state is RED, when the
Red LED line is in the active state the LED state is GREEN.!
Section continued on next page.
Switch /
Address
1
2
3
0 /
configurable
1
X
2
X
3
X
X
4
X
5
X
X
6
X
X
7
X
X
X

Page 17
DIP Switch 5 - Enabling Beep on Read: !
When DIP Switch 5 is ON and the OSM-2400 is in ACU mode, every time the OSM-2400 receives
card or keypad data it will also send the OSDP reader (PD) the osdp_BUZZ command with a 500
ms (0.5 second) activation time. !
DIP Switch 5 has no function in PD Mode. !
DIP Switch 6 - Require Secure Channel Communication:
In PD Mode, when DIP Switch 6 is ON, the OSM-2400 will only reply to attempts by the ACU to
start a Secure Channel communication session. The OSM-2400 will reply to all other commands
sent by the ACU in clear channel with a NAK. Once a Secure Channel session is established, the
OSM-2400 will behave as a normal PD.!
In ACU Mode, when DIP Switch 6 is ON, the OSM-2400 will only attempt to start a Secure Channel
session with the PD. Once a Secure Channel session is established, the OSM-2400 will behave as
a normal ACU.!
DIP Switch 7 - Invert LED I/O Pin State:
When DIP switch 7 is ON, the states of the LED lines will be inverted, making the LED lines active
high digital inputs. The active state is high (5V) and the normal state is low (0V).!
DIP Switch 8 - ACU Mode / PD Mode Select: !
When DIP switch 8 is ON the OSM-2400 will operate in ACU Mode. When DIP switch 8 is OFF the
OSM-2400 will operate in PD Mode. !
Cypress OSM-2400 Manual - DIP Switches (Cont.)

Page 18
Cypress OSM-2400 Manual - LED Modes
The OSM-2400 supports two LED modes which are used to support different types of LED control
in OSDP readers or ACUs (Access Control Unit). The LED mode is selected with DIP Switch 4.
When DIP Switch 4 is OFF the OSM-2400 is in Dual LED Mode. When DIP Switch 4 is ON the
OSM-2400 is in Single LED Mode. The Red and Green LED lines are active low digital I/O lines. The
LED lines are in the normal state at 5V, and are in the active state when they are at 0V. !
Dual LED Mode
In Dual LED Mode the Red and Green LED lines are enabled and there are four possible LED
states; RED, GREEN, AMBER ,and OFF. The table below shows the different states of the Red and
Green LED lines and how those states correspond to the LED color. The default LED state, when
no LED lines are asserted, is OFF.
Command Color
Red LED Line State
Green LED Line State
OFF
Normal
Normal
RED
Active
Normal
GREEN
Normal
Active
AMBER
Active
Active
Single LED Mode !
In Single LED Mode the Red LED line is enabled and the Green LED line is disabled. There are two
possible LED states; RED and GREEN. The OSDP spec does not allow a PD (OSM-2400) to NAK
an LED command with the color OFF, so in this case the OSM-2400 will put the Red LED line in the
normal state. The table below shows the different states of the Red LED line and how those states
correspond to the LED color. The normal state is RED and the active state is GREEN.
Command Color
Red LED Line State
OFF (RED)
Normal
RED
Normal
GREEN
Active

Page 19
Cypress OSM-2400 Manual - LED Modes (Cont.)
When DIP switch 7 is ON, the state of the LED lines are inverted. The tables below show the state
of the Red and Green LED Lines when DIP switch 7 is ON.
Command Color
Red LED Line State
Green LED Line State
OFF
Active
Active
RED
Normal
Active
GREEN
Active
Normal
AMBER
Normal
Normal
Dual LED Mode Red and Green LED Line States (DIP switch 7 ON / Inverted)
Single LED Mode Red and Green LED Line States (DIP switch 7 ON / Inverted)
Command Color
Red LED Line State
OFF (RED)
Active
RED
Active
GREEN
Normal

Page 20
Cypress OSM-2400 Manual - Using Secure Channel Communication
Secure Channel Mode
The OSM-2400 is in Secure Channel Mode when DIP Switch 6 is ON or when the Secure Channel
Base Key (SCBK) has been set by the user. While the OSM-2400 is in Secure Channel Mode, the
OSM-2400 will limit its functionality until a Secure Channel session is established. If the SCBK has
not been set by the user, the OSM-2400 uses the SCBK-D (default SCBK). !
ACU Mode - When Secure Chanel Mode is not active, the OSM-2400 will initiate an unencrypted
session with the OSDP reader or PD (Peripheral Device). When Secure Channel Mode is active, the
OSM-2400 will only attempt to establish a Secure Channel session with the PD. !
PD Mode -When Secure Channel Mode is not active, the ACU (Access Control Unit) can initiate an
unecrypted session or Secure Channel session with the OSM-2400. When Secure Channel Mode is
active, the OSM-2400 will only process a subset of commands (listed below), until the ACU
establishes a Secure Channel session with the OSM-2400.!
•osdp_ID!
•osdp_CAP!
•osdp_COMSET!
•osdp_CHLNG!
•osdp_MFG!
Setting the Secure Channel Base Key (SCBK)
From the factory, the OSM-2400 is loaded with the SCBK-D, as defined in the OSDP specification.
The SCBK-D / SCBK is used to encrypt the data payload of OSDP messages while in a Secure
Channel session. The OSM-2400 SCBK-D is 30 31 32 33 34 35 36 37 38 39 3A 3B 3C 3D 3E 3F
(16 bytes in HEX) and is public. !
IMPORTANT: It is strongly recommended that a new SCBK be set in the OSM-2400 when using
Secure Channel communication in ACU Mode or PD Mode. The SCBK is set in while the
OSM-2400 is in PD Mode. The OSM-2400 will only accept the osdp_KEYSET command while it is
in a Secure Channel communication session with an ACU. This means the current SCBK must be
known before a new SCBK can be set in the OSM-2400.!
The ACU sends the osdp_KEYSET command with the new SCBK to the OSM-2400 while in a
Secure Channel communication session. It is best practice for the SCBK to be sent to the
OSM-2400 out-of-band, meaning the OSM-2400 is directly connected to the ACU over a short run
of cable and not connected to the ACU over the OSDP network connection. If an attacker is able to
listen in on the OSDP communication while the osdp_KEYSET command is sent from the ACU to
the OSM-2400 in PD Mode, they will have the SCBK and be able to decrypt the OSDP messages. !
Section continued on next page.