Справочник Пользователя для IBM EasyCoder 3400e
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Communications Reference
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Communication Protocols
Communication protocols are important because they determine the transmission
standards for communication between the printer and the host. The printer and the host
must use the same protocol and parameters to communicate properly. The printer
supports the flow control and block transfer protocols described in the next sections.
All of these protocols are point-to-point except Multi-Drop. Application programs
and/or ROM BIOS determine which protocols your computer can support. For more
detailed information, refer to the Intermec Data Communications Reference Manual
(Part No. 044737).
standards for communication between the printer and the host. The printer and the host
must use the same protocol and parameters to communicate properly. The printer
supports the flow control and block transfer protocols described in the next sections.
All of these protocols are point-to-point except Multi-Drop. Application programs
and/or ROM BIOS determine which protocols your computer can support. For more
detailed information, refer to the Intermec Data Communications Reference Manual
(Part No. 044737).
Intermec Standard Protocol
Intermec Standard protocol is a proprietary block transfer/status response protocol. For
each block sent, the host must wait for the appropriate response before sending the next
block (<DC1>). Except for single character status commands (<ENQ> and <VT>),
Standard protocol transmits characters in message blocks beginning with the start of
text (<STX>) character and ending with the end of text (<ETX>) character. Message
blocks can be up to 255 characters, including the start of text and end of text characters.
The printer auto-discriminates between Standard, Polling Mode D, and Multi-Drop
protocols.
each block sent, the host must wait for the appropriate response before sending the next
block (<DC1>). Except for single character status commands (<ENQ> and <VT>),
Standard protocol transmits characters in message blocks beginning with the start of
text (<STX>) character and ending with the end of text (<ETX>) character. Message
blocks can be up to 255 characters, including the start of text and end of text characters.
The printer auto-discriminates between Standard, Polling Mode D, and Multi-Drop
protocols.
The printer returns its highest priority status when it receives a valid block (<STX>
data <ETX>) or when it receives the status request command <ENQ>. When the printer
receives the status dump command (<VT>), the printer returns all active status. The
printer status response time ranges from 30ms to 100ms depending on the complexity
of the received message block. In the case of a transmission error, the printer responds
with a <NAK> and discards the entire message block.
data <ETX>) or when it receives the status request command <ENQ>. When the printer
receives the status dump command (<VT>), the printer returns all active status. The
printer status response time ranges from 30ms to 100ms depending on the complexity
of the received message block. In the case of a transmission error, the printer responds
with a <NAK> and discards the entire message block.
The table below shows printer status conditions in descending order of priority, status
response characters, and pin 11/20 states:
response characters, and pin 11/20 states:
Printer Status
Character
Pin 11/20
Buffer already full
GS
Busy
Ribbon fault
US
Busy
No label stock
EM
Busy
Buffer now full
DC3
Busy
Printhead hot
SI
Busy
Offline (paused)
DC3
Busy
Label at strip pin
FS
Ready
Skipping
DC1
Ready
Printing
DC1
Ready
Ready/Online
DC1
Ready
Note: Do not confuse the Buffer now full <DC3> status with the XON/XOFF
characters <DC1> and <DC3>.
characters <DC1> and <DC3>.