Symbol Technologies LS 1000 Software Handshaking

4-35

LS 1000 Product Reference Guide: Chapter 4, Programming the LS 1004

Software Handshaking

This parameter offers control of the data transmission process in addition to, or instead

of, that offered by hardware handshaking. These options may be combined; for

example, ACK/NAK with ENQ.

• No software handshaking

• ACK/NAK only

The ACK/NAK option checks the success or failure of transmission. The scanner

expects one of the following host responses after a data transmission:

<ACK> acknowledges a valid and successful transmission.

<NAK> indicates a problem with the transmission.

Whenever a NAK is received, the unit retransmits the same data and awaits an

ACK/NAK response. After three unsuccessful attempts to transmit the same

data, the scanner aborts any further communication attempts of that message.

• ENQ ONLY

The ENQ option needs the host to request data before it is transmitted to the host.

This ensures that data transmission occurs only when the host is ready to receive.

When you select the wait for ENQ option, the scanner waits for an ENQ from the

host before it transmits data; otherwise, the unit transmits data without waiting

for an ENQ character from the host. With ENQ enabled, the scanner must receive

an ENQ from the host within a 2-second period after the last activity, or a

None

ACK/NAK

coverBook Page 35 Monday, December 1, 1997 2:19 PM

Contents

Main LS 1000 Product Reference Guide Page Factory Service Symbol Support Center SYMBOL SUPPORT CENTER 1-800-653-5350 Contents Chapter 4. Programming The LS 1004 Chapter 3. Maintenance & Specifications Chapter 2. Scanning Page Chapter 1 Introduction and Set-up Introduction Page Set-Up LS 1000 Product Reference Guide: Chapter 1, Introduction and Setup Switching Cables Connecting to a Host For external power operation with Synapse Smart Cable RS-232C Page Page RS-232C (Contd) For battery operation: IBM 468X/9X IBM 468X/9X (Contd) Page Page Ready, Test, Scan Aiming Scan the Entire Symbol Hold at an Angle Page Maintaining the LS 1000 Scanner Recharging a Nickel-Cadmium Battery Changing the Battery Battery Box Operation Maintenance Accessories Optional Accessories Required Accessories What If... 3-6 LS 100x Technical Specications Depth of Field in Inches/Centimeters Figure 3-1. LS 100x Decode Zone LS 100x Decode Zone 3-7 Table 3-1. Technical Specications (LS 1000) 3-8 Table 3-1. Technical Specications (LS 1000) (Continued) 3-9 Table 3-2. Technical Specications (LS 1004) Page Page 3-12 * active low Table 3-4. Pinouts - LS 1004 3-13 Table 3-5. Beeper Indications Page 4-2 4-3 4-4 Scanning Sequence Scanning Sequence Example Errors While Scanning Parameter Descriptions Set Parameter Defaults Host Interface Select Page Page Decode Attempt Time Page Transmit No Decode Message Decode Redundancy Code Types UPC/EAN Convert UPC-E to UPC-A EAN Zero Extend Decode UPC/EAN Supplemental UPC A and E Preamble(s) UPC-E Pream- UPC-A Pream- UPC/EAN Security Level Code 128 Enable/Disable Code 128 Send CODE 128 Function Character Code 39 Page Interleaved 2 of 5 Enable/Disable Code I 2 of 5 Fixed Lengths for Code I 2 of 5 4-22 Fixed Lengths for Code 2 of 5 (contd) I 2 of 5 Modulo 10 Check ITF14/EAN13 Conversion Discrete 2 of 5 Enable/Disable D 2 of 5 D 2 of 5 Modulo 10 Check Fixed Lengths for Code 2 of 5 4-25 Fixed Lengths for Code 2 of 5 (contd) Codabar Data Options Transmit Code ID Character Prex Sufx 4-30 Prex/Sufx Values RS-232C Baud Rate Parity Data Format Stop Bit Select Check Parity Hardware Handshaking Software Handshaking Page 4-37 Hardware and Software Handshaking Sequence HARDWARE HANDSHAKING SOFTWARE HANDSHAKING Page 4-39 Intercharacter Delay Values (contd) Chapter 5 Glossary Page Page Page 6-1 Chapter 6 ASCII Character Set ASCII Character Set Table 6-1. ASCII Character Set 6-2 PPT 4600 Product Reference Guide: Getting Started Table 6-1. (Continued) ASCII Character Set 6-3 PPT 4600 Product Reference Guide: Getting Started Table 6-1. (Continued) ASCII Character Set A-1 Appendix A Errata Table A-1. ASCII Character Set A-2 A-3 Page Tell Us What You Think...