17: USER COMMUNICATION INSTRUCTIONS17-32 « FC4A MICRO SMART USER ’S MANUAL »Sample Program – User Communication TXDThis example demonstrates a program to send data to a printer using the user communication TXD2 (transmit) instruction,with the optional RS232C communication adapter installed on the port 2 connector of the 24-I/O type CPU module.System SetupThe name of BUSY terminal differs depending on printers, such as DTR. The function of this terminal is to send a signalto remote equipment whether the printer is ready to print data or not. Since the operation of this signal may differ depend-ing on printers, confirm the operation before connecting the cable.Description of OperationThe data of counter C2 and data register D30 are printed every minute. A printoutexample is shown on the right.Programming Special Data RegisterSpecial data register D8105 is used to monitor the BUSY signal and to control thetransmission of print data.The MicroSmart monitors the DSR signal to prevent the receive buffer of the printer from overflowing. For the DSR sig-nal, see page 17-30.Special DR Value DescriptionD8105 3While DSR is on (not busy), the CPU sends data.While DSR is off (busy), the CPU stops data transmission.If the off duration exceeds a limit (approx. 5 sec), a trans-mission busy timeout error will occur, and the remainingdata is not sent. The transmit status data register storesan error code. See pages 17-11 and 17-27.To RS232C PortD-sub 9-pin Connector PinoutsPin Description1 NC No Connection2 NC No Connection3 DATA Receive Data4 NC No Connection5 GND Ground6 NC No Connection7 NC No Connection8 BUSY Busy Signal9 NC No ConnectionPrinterMini DIN Connector PinoutsDescription Color PinShield — CoverNC No Connection Black 1NC No Connection Yellow 2TXD Transmit Data Blue 3NC No Connection Green 4DSR Data Set Ready Brown 5NC No Connection Gray 6SG Signal Ground Red 7NC No Connection White 8User Communication Cable 1CFC2A-KP1C2.4m (7.87 ft.) longAttach a proper connector to the openend of the cable referring to the cableconnector pinouts shown below.Cable Connection and PinoutsTo Port 2 (RS232C)RS232C Communication AdapterFC4A-PC1Caution • Do not connect any wiring to the NC (no connection) pins; otherwise, the MicroSmart and theprinter may not work correctly and may be damaged.--- PRINT TEST ---11H 00MCNT2...0050D030...3854--- PRINT TEST ---11H 01MCNT2...0110D030...2124Printout Example
