GTCO CalComp CR-1212 User Manual

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Chapter 1

Chapter 2

Chapter 3

Chapter 4

What is the CR 1212 and How Does It Work?

Section A: What is the CR 1212?
Section B: How the CR 1212 Works
Section C: Commands: Controlling the Tablet’s Operation
Section D: Alternative Configurations

Assembly and Installation

Interfacing with the Host

Section A: Hardware Interfaces
Section B: Baud Rate
Section C: Communication Protocols
Section D: Report Formats

Operating Characteristics and Functions

Section A: Controlling the Report Flow

Point Mode
Remote Request Mode
Stream Mode
Switch Stream Mode
Report Rate
Increment Mode

Section B: Setting the Resolution

Resolution, Predefined
Resolution, Definable (Set X, Y Scale)

Section C: Other Functions

Bit Pad Configuration
Origin
Relative Coordinates (Delta Mode)
Reset (to Default Operating Characteristics)
Send Configuration

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Chapter 5

Chapter 6

Chapter 7

Chapter 8

Appendix A

Appendix B

Tablet Beep
Transmission Control

Section D: Reserved Commands

Guidelines for Writing a Device Driver

Using the CR 1212

Checking the Graphics Tablet

Section A: Tablet Calibration
Section B: Power (and Proximity) Light
Section C: A Quick Functional Check
Section D: Diagnostic Functions

Echo
Self-Test

Operating Environment, Care and Service

Section A: Operating Environment
Section B: Service
Section C: Care and Cleaning
Section D: Changing the Stylus Refill

Specifications

ASCII Conversion Chart

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Chapter 1: What is the CR 1212 and How Does It Work?

Section A: What is the CR 1212?

CR 1212 is a graphics tablet that acts as an input device. It allows for the translation of
graphic information into digital, suitable for a digital device such as a computer.

 Steering a computer screen pointer
 Selecting locations on menus
 Drawing and tracing

The components required for a functional CR 1212 are:

 Tablet
 Stylus or cursor
 Interface cable
 Power source

The tablet is similar to a drawing board. The stylus and cursor are handheld devices that
are used for pointing or drawing on the tablet. The interface cable connects the graphics
tablet to the host (computer).

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Section B: How the CR 1212 Works

CR 1212 translates the stylus/cursor position on the tablet into digital information and
communicates it to the host. The stylus/cursor position is expressed as an X, Y coordinate
pair. One coordinate pair is a report.

Valid reports can only be collected when the stylus/cursor is in the tablet’s active area and

in proximity:

 Active area is a 12-inch square area inside the groove on the tablet surface.
 Proximity is the maximum distance above the active area that the stylus/cursor can

be held and report a valid position. It’s approximately ½ inches, which means the

stylus/cursor and tablet do not need to be in direct contact with each other to issue
reports. There still can be up to a ½ inch of material (drawings, photos, etc.)
between the tablet and stylus/cursor, allowing it to issue reports.

The active area and proximity, in effect, establish a three-dimensional volume within which
the stylus/cursor can issue valid reports. Reports issued from outside of this volume are
out-of-prox and, therefore, do not represent the current position of the stylus/cursor.

Reports are measured in counts of resolution. Resolution is the fineness of detail that the

tablet can distinguish. It’s expressed in lines per inch (lpi) or lines per millimeter (lpmm).
This is slightly misleading, however. Resolution should be expressed in “bands per …” or
“lanes per …” because these lines have perceivable width at lower resolution settings.

The higher the resolution, e.g. 100 lpi or 200 lpi, the narrower the bands of resolution
become. Eventually, the bands become so narrow that they are easier to conceptualize as
lines of no measurable width.

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As previously stated, reports are measured in counts of resolution. As shown below, each
square is one count of resolution. The tablet reports the same coordinates for any point
within the square.

With different resolution settings, you can receive different reports for the same tablet
location. In the illustration below, points A and B are the same physical locations on the
tablet, but their coordinates are different because of the resolution setting.

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Reports are in absolute or relative coordinates. Absolute coordinates are coordinates
measured from the tablet’s origin (0, 0). Relative coordinates are measured relative to the
last report location. In the illustration above, point B is issued after point A. Therefore, in
relative coordinates, point B is measured relative to point A.

The tablet defaults to absolute coordinates. However, you can change to relative
coordinates with the Relative Coordinates command, described in Chapter 4.

Section C – Commands: Controlling the Tablet’s Operation

Control the CR 1212’s operating characteristics, functions and diagnostics with commands
from the host. This book represents the commands in ASCII. For convenience, an ASCII
conversion chart appears in Appendix B.

The tablet accepts commands from the host at any rate, except as follows:

 After turning on the tablet, wait approximately 300 milliseconds before sending

commands.

 Commands that require a tablet response: If you send a command to the tablet that

requires a response, the tablet does so within two milliseconds. Wait until the host
receives the entire response before issuing another command to the tablet.

 Definable Resolution (Set X, Y Scale): After issuing the Definable Resolution

command, wait for at least 0.5 milliseconds before issuing another command to the
tablet.

Section D: Alternative Configurations

CR 1212 comes in three operational configurations: Bit Pad One, Bit Pad Two and CR. The
standard configuration is Bit Pad One. The other configurations are special orders.

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 Tablet
 Stylus or cursor

 Interface cable
 CR 1212 Graphics Tablet User’s Guide

Chapter 2: Assembly and Installation

The CR 1212 package should include the following:

To assemble and install CR 1212:

1. Connect the stylus/cursor to the tablet.

2. Attach the tablet to the host and power source.

3. Turn on the tablet.

NOTE: Always have the computer and tablet power off when attaching or detaching any
part of the CR 1212. If the power is on, nothing serious happens to the CR 1212, but it
could have the potential to corrupt the file being worked on or cause the computer to
malfunction.

Installing CR 1212 Graphics Tablet

1. Plug the stylus/cursor into the phone socket on the right-hand edge of the tablet.

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The cursor and stylus are interchangeable. However, before changing from one to the
other, turn off the tablet. (This allows the tablet’s internal software to re-initialize for each
device.)

2. Plug the 8-pin phone connector on the interface cable into the tablet.

3. Connect the 25-pin D connector of the interface cable into the host communications

port.

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4. Plug the power supply barrel connector into the interface cable’s D connector.

5. Plug the power supply into a grounded electrical outlet. Use only a CR 1212 power

supply. Substituting a different power supply could permanently damage the
graphics tablet.

6. Turn the tablet on.

Turn the power (ON/OFF) switch on. The tablet calibrates itself. This takes approximately
three seconds and once the calibration is complete, the tablet beeps.

The power light is lit when the tablet is on. It’s also a proximity indicator that remains lit
when the stylus/cursor is in-prox. It blinks when the stylus/cursor is out-of-prox. If the
light blinks when the stylus/cursor is in-prox, then the tablet is malfunctioning. Turn it off
for 10 or 20 seconds, and then turn it on again. If it fails again, have it serviced.

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Chapter 3: Interfacing with the Host

For successful communication between the CR 1212 and its host, they must have the same
hardware interface, baud rate, communications protocol and report format.

Section A: Hardware Interface

The hardware interface for the CR 1212 is an RS-232C with a 25-pin D connector. The pin
assignments are listed below.

RS-232C Interface: 25-Pin D Connector Pin Assignments

The computer must have an RS-232C communications port terminated with a 25-pin male
D connector that is configured as DTE (Data Terminal Equipment).

NOTE: If the computer has a different connector, contact your GTCO CalComp by Turning
Technologies representative for information about adapter cables.

The CR 1212 complies with standard signal levels for data transmission:

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RS-232C Signal Levels

NOTE: The source is the EIA Standard RS-232C: Interface between Data Terminal
Equipment and Data Communication Equipment Employing Serial Binary Data
Interchange, by the Engineering Department of the Electronics Industries Association

(Washington, D.C.: EIA, 1969).

Section B: Baud Rate

The CR 1212 is available with 9600 baud or Autobaud. The standard setting is 9600 baud,
unless Autobaud is specifically ordered.

Autobaud automatically matches the tablet baud rate to the host baud rate. The tablet
supports 9600, 4800, 2400 and 1200 baud. With Autobaud, you must send an ASCII space
(SP) to the tablet just after starting it. The tablet uses this character to identify the host
baud rate. The tablet then sets its baud rate and issues an ASCII acknowledge (ACK) to the
host.

Section C: Communication Protocols

The CR 1212 communication protocols are:

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Section D: Report Formats

The CR 1212 has one of the following report formats:

 Bit Pad One-compatible format (default)
 Bit Pad Two-compatible format
 CR format (similar to MM packed binary format)
 Bit Pad One- or Two-compatible format for Relative Coordinates (Delta Mode)
 CR format for Relative Coordinates (similar to MM packed binary format for Delta

Mode)

The report formats are in (packed) binary. The reports are in counts of resolution, not in
inches or millimeters.

Bit Pad One-Compatible Report Format

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Bit Pad Two-Compatible Report Format

CR Report Format

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Bit Pad One- or Two-compatible format for Relative Coordinates

CR Format for Relative Coordinates

Key:

 LSB is the least significant bit. MSB is the most significant bit.

 Fa, Fb, Fc and Fd are the flag bits. They identify the status of the stylus tip and

cursor buttons:

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*Output for Bit Pad One or Two configurations using absolute coordinates.

**Output for Bit Pad One or Two configurations using relative coordinates.

 Sx and Sy are the X and Y coordinate signs. 1 is positive and 0 is negative.

 PR is the proximity bit. 0 is in-prox and 1 is out-of-prox.

 PH is the phasing bit, which is always 1.

 X0, X1, etc. and Y0, Y1, etc. are the X and Y coordinate bits.