Getting Started

Note
Through out all pages relating to RS232 communications, reference is made to SharpEdit (an application by SharpCam Ltd that is an editor that also has RS232 communications). SharpEdit's RS232 communications works identically to SharpCam, the two terms can be used interchangeably, except that SharpCam cannot receive programs from a machine. Any references to receiving should be ignored with respect to SharpCam. All RS232 settings are shared between SharpEdit and SharpCam.

If you intend to use SharpEdit to send and receive programs you will need to set up SharpEdit and/or your machine tool.

Note:
The information provided is intended to supplement the documentation provided by the machine tool builder and should not be considered a replacement. It is your responsibility to ensure that any changes made to the machine parameters/settings are correct, and that any cabling is wired correctly, so as not to cause damage or loss of data.

Cable

The quality of the cable used is very important. In an environment such as a factory we recommend a cable that is specifically designed for RS232 communications. This type of cable typically is 'Overall foil shielded', has 6 non paired conductors (stranded) of 24 AWG (0.21mm2), and has a low capacitance. These properties can be found in Belden 9536 cable or equivalent.

Cable Connections

Below is a generic cable that should work with most machines. If we have had experience of successful communications for a particular control the connections are detailed separately under their respective sections.

Machine End Pin No
DB 25 connector
Computer End Pin No
DB 9 connector
1* Do NOT connect
2 2
3 3
4 8
5 7
7 5
6, 8 and 20 linked together

*There should be an uninsulated wire between the outer jacket and the foil shield. Connect this wire to pin 1 at the machine end only. Never connect to pin 1 at both ends or a ground loop can occur.

This cable is suitable for Software (XOn/XOff) and Hardware (Rts/Cts) Hand Shaking.

Character Set

SharpEdit supports the ASCII/ISO character set. EIA is not supported.

RS232 Ports (Serial Ports)

Computer

The computer can be fitted with a 25 or 9 pin male connector, but, due to the system requirements of SharpEdit, only a 9 pin connector will be fitted.
You may see a 25 pin female connector, this is the parallel port and typically used for printing. Under no circumstances use this port or damage may result.

Just to confuse matters, serial ports are not always fitted:

Laptops - are not fitted with a serial port anymore.
If the laptop is fitted with a PCMCIA slot (also known as PC Card) then a PCMCIA to RS232 Serial Port adapter is required. Ensure drivers are available for your version of Windows.
If the laptop is fitted with an ExpressCard slot, then an ExpressCard to RS232 Serial Port adapter is required. Some adaptors are based on an USB interface and therefore do not meet the hardware requirements. Ensure drivers are available for your version of Windows.

Desktop - not all new computers are fitted with a serial port. This can be easily remedied by fitting a RS232 serial port card into a spare expansion slot.

USB to Serial Port adaptors - These adaptors are just not reliable enough and therefore do not meet the hardware requirements for use with SharpEdit as specified by the Hardware Requirements.

Machine/Control

A 25 pin D connector is fitted to the machine. Typically a female connector is fitted, but there are exceptions.

Setting the communication parameters

Before you can start communicating with your machine, there are a number of settings that need to be matched between the machine and SharpEdit.
To access the settings, from SharpCam select the RS232 Settings command from the Tools Menu, from SharpEdit select the RS232 Settings command from the Communications Menu. From here you can create or edit machine settings.

Com Port

The Com Port refers to the name of the physical connection on the PC that the cable plugs into. If you have a desktop PC or an older laptop that has a serial port, then the name is typically COM1 or COM2. PCMCIA/ExpressCard adaptor tend to use COM3 and above.
When setting the Com Port to use in SharpEdit, only the available ports are listed. If COM1 is listed then try this first, if you are using a PCMCIA/ExpressCard adaptor then it is best to use the Device Manager to determine the name of the port.

Baud Rate

The Baud Rate determines the speed at which the Nc code is transmitted. This value must be the same at the machine and at SharpEdit. You can either change SharpEdit to match the machine or change the machine to match SharpEdit. A good starting rate is 9600, see the documentation for your machine to establish how to change/check the baud rate setting.

Parity

The parity settings must match. Not all machines allow this to be changed, so typically you must change SharpEdit to match the machine. See the documentation for your machine to establish how to check the parity requirements.

Hand Shaking

The hand shaking determines how the flow of data is controlled. There are two types (apart from None, which is not recommended), Software and Hardware. Software is called XOnXOf and Hardware RtsCts in SharpEdit. See the documentation for your machine to establish what hand shaking is available. Typically most machines use Software hand shaking. Hardware hand shaking requires additional connections in the cable.

Data Bits

The data bits settings must match. Not all machines allow this to be changed, so typically you must change SharpEdit to match the machine. See the documentation for your machine to establish how to check the data bits requirements.

Stop Bits

The stop bits settings should be matched. See the documentation for your machine to establish how to change/check the stop bits.

Other Settings

There a number of other settings available, most of which will not be needed. You must set Characters to send at end of line, see below.

Characters to send at end of line

Typically a carriage return and line feed are required. To specify a character(s) first choose the desired character from the ASCII Table Enclose the corresponding decimal value for each character in <> brackets, without any form of punctuation in between. For example: <13> for carriage return and <10> for line feed. This is the default when you create a new RS232 Settings for a machine.