Serial Interface 7 - 13
Software Handshaking
This parameter offers control of data transmission in addition to, or instead of, the control hardware handshaking
offers. There are five options.
If software handshaking and hardware handshaking are both enabled, Hardware Handshaking takes precedence.
•
None
: Data transmits immediately. No response is expected from host.
•
ACK/NAK
: After transmitting data, the decoder expects either an ACK or NAK response from the host. When
the decoder receives a NAK, it transmits the same data again and waits for either an ACK or NAK. After three
unsuccessful attempts to send data when NAKs are received, the decoder issues an error indication and
discards the data.
The decoder waits up to the programmable Host Serial Response Time-out to receive an ACK or NAK. If the
decoder does not receive a response in this time, it issues an error indication and discards the data. There
are no retries when a time-out occurs.
•
ENQ
: The decoder waits for an ENQ character from the host before transmitting data. If the decoder does not
receive an ENQ within the Host Serial Response Time-out, it issues an error indication and discards the data.
The host must transmit an ENQ character at least every Host Serial Response Time-out to prevent
transmission errors.
•
ACK/NAK with ENQ
: This combines the two previous options. For re-transmissions of data due to a NAK
from the host, an additional ENQ is not required.
•
XON/XOFF
: An XOFF character turns the decoder transmission off until the decoder receives an XON
character. There are two situations for XON/XOFF:
•
The decoder receives an XOFF before it has data to send. When the decoder has data to send, it waits up
to the Host Serial Response Time-out for an XON character before transmission. If it does not receive an
XON within this time, the decoder issues an error indication and discards the data.
•
The decoder receives an XOFF during a transmission. Data transmission then stops after sending the
current byte. When the decoder receives an XON character, it sends the rest of the data message. The
decoder waits indefinitely for the XON.
Summary of Contents for Symbol PL4507
Page 1: ...Symbol PL4507 Decoder Integration Guide ...
Page 2: ......
Page 3: ...Symbol PL4507 Decoder Integration Guide 72E 116649 02 Revision A April 2009 ...
Page 6: ...iv Symbol PL4500 Decoder Integration Guide ...
Page 16: ...xiv Symbol PL4507 Decoder Integration Guide ...
Page 20: ...xviii Symbol PL4507 Decoder Integration Guide ...
Page 40: ...2 12 Symbol PL4507 Decoder Integration Guide ...
Page 43: ...Accessories 3 3 Figure 3 2 Symbol SE4500 to PL4507 21 Pin Flex p n 15 113896 01 ...
Page 45: ...Accessories 3 5 Figure 3 4 Symbol PL4507 30 Pin Mating Host Connector p n 50 12167 030 ...
Page 70: ...4 24 Symbol PL4507 Decoder Integration Guide ...
Page 122: ...6 20 Symbol PL4507 Decoder Integration Guide ...
Page 146: ...7 24 Symbol PL4507 Decoder Integration Guide ...
Page 168: ...8 22 Symbol PL4507 Decoder Integration Guide ...
Page 256: ...9 88 Symbol PL4507 Decoder Integration Guide ...
Page 264: ...10 8 Symbol PL4507 Decoder Integration Guide ...
Page 289: ...Advanced Data Formatting 11 25 Numeric Keypad continued 7 8 9 Cancel ...
Page 334: ...11 70 Symbol PL4507 Decoder Integration Guide Send ALT Characters continued Send Alt Send Alt ...
Page 355: ...Advanced Data Formatting 11 91 Alphanumeric Keyboard Space Single Close Quote Dash ...
Page 357: ...Advanced Data Formatting 11 93 Alphanumeric Keyboard continued ...
Page 358: ...11 94 Symbol PL4507 Decoder Integration Guide Alphanumeric Keyboard continued _ Underscore ...
Page 360: ...11 96 Symbol PL4507 Decoder Integration Guide Alphanumeric Keyboard continued 6 7 8 9 A B C ...
Page 361: ...Advanced Data Formatting 11 97 Alphanumeric Keyboard continued D E F G H I J ...
Page 362: ...11 98 Symbol PL4507 Decoder Integration Guide Alphanumeric Keyboard continued K L M N O P Q ...
Page 363: ...Advanced Data Formatting 11 99 Alphanumeric Keyboard continued R S T U V W X ...
Page 365: ...Advanced Data Formatting 11 101 Alphanumeric Keyboard continued d e f g h i j ...
Page 366: ...11 102 Symbol PL4507 Decoder Integration Guide Alphanumeric Keyboard continued k l m n o p q ...
Page 367: ...Advanced Data Formatting 11 103 Alphanumeric Keyboard continued r s t u v w x ...
Page 368: ...11 104 Symbol PL4507 Decoder Integration Guide Alphanumeric Keyboard continued y z ...
Page 380: ...A 12 Symbol PL4507 Decoder Integration Guide ...
Page 389: ...Sample Bar Codes C 3 Data Matrix Maxicode ...
Page 390: ...C 4 Symbol PL4507 Decoder Integration Guide ...
Page 394: ...D 4 Symbol PL4507 Decoder Integration Guide ...
Page 414: ...Glossary 8 Symbol PL4507 Decoder Integration Guide ...
Page 422: ......
Page 423: ......