GoOn-GoOff

GoOn-GoOff (gongoff) is a go implementation of the Epson Xon-Xoff protocol.

It's used to communicate with fiscal printers that support the Xon-Xoff protocol.

Supported connections: serial and network

Supported platforms: Windows, Linux, macOS, Android (only network), iOS (only network)

How to use

• Create a Printer object and call Open()
• Create the Documents or Commands objects that fit your needs
• Use the functions PrintCommands([]Command) or PrintDocument(Document) to execute the commands

Documents

Documents are a set of commands commonly sent to a printer together.

Supported documents are:

• DocumentCommercial (fiscal receipt)
• DocumentManagement
• DocumentCommercialReturn
• DocumentCommercialCancellation
• DocumentPOSReturn
• DocumentPOSCancellation
• DocumentInvoice
• DocumentCommercialWithInvoice

Commands

Commands are a less abstract way to use the library and allow to use all the features of Xon-Xoff.

There are a handful of commands with predefined implementations. All the other commands can be created using a GenericCommand with the appropriate parameters and terminator.

Usage examples

Printing a test document through serial port (RS-232)

// Create a SerialPrinter object and open the serial port COM3. 
printer := gongoff.NewSerialPrinter("COM3")
err := printer.Open()
if err != nil {
    panic(err)
}
defer printer.Close()

// Create a management document.
doc := gongoff.NewDocumentManagement([]string{"test", "test2", "test3"})

// Print it.
err = printer.PrintDocument(doc)
if err != nil {
    panic(err)
}

Printing a commercial document (fiscal receipt) through network

// Create a NetworkPrinter object and open the connection.
printer := gongoff.NewNetworkPrinter("192.168.1.100", 9100)
err := printer.Open()
if err != nil {
    panic(err)
}
defer printer.Close()

// Create a receipt document.
// In this example, the document is a 7,50 euro receipt for a product called "Bread" paid with cash.
testProduct := "BREAD"
commandProduct := gongoff.NewCommandProduct(750, &testProduct, nil, nil)
commandPayment, err := gongoff.NewCommandPayment(gongoff.TerminatorTypePaymentCash, nil, nil)
if err != nil {
	panic(err)
}
commercialDoc := gongoff.NewDocumentCommercial(
    []gongoff.CommandProduct{
        *commandProduct,
    },
    []gongoff.CommandPayment{
        *commandPayment,
    },
    nil,
    nil,
    nil,
    nil,
)

// Print it.
err = printer.PrintDocument(commercialDoc)
if err != nil {
    panic(err)
}

Showing test message on the display

// Suppose the printer object is already created and opened.
// Since there is no document that fits our needs, we use an array of commands.
commandFirstLine := gongoff.NewCommandDisplayMessage("First line", 1)
commandSecondLine := gongoff.NewCommandDisplayMessage("Second line", 2)

// Print the commands.
err := printer.PrintCommands([]gongoff.Command{commandFirstLine, commandSecondLine})
if err != nil {
    panic(err)
}

Print financial report with zeroing

// Suppose the printer object is already created and opened.
// Since there is neither a document nor a command that fits our needs, we generate a generic command with the right terminator.
var commands []gongoff.Command
terminator := gongoff.NewTerminator(nil, gongoff.TerminatorTypeFinancialReportZeroing)
commands = append(commands, 
	gongoff.NewCommandGeneric(
            []gongoff.Data{},
            *terminator, 
	),
)

// Print the commands.
err := printer.PrintCommands(commands)
if err != nil {
    panic(err)
}