Asynchronous Terminals and Printer Processes Programming Manual

PROCEDURE CALLS FOR ACCESSING TERMINALS
Page Mode
S5073-002
Application I/O Process LIU Device
WRITE
(Screen)
READ
(Function key)
WRITE
WRITE
Completion
READ
WRITE
(EOT)
WRITEREAD
(Block 1)
WRITEREAD
(Block 2)
WRITEREAD
(Last block)
WRITE
Completion
WRITE
(EOT)
WRITEREAD
(ENQ)
WRITEREAD
(ACK)
READ
Completion
ACK
ACK
ACK
Function Key
EOT
READ
Completion
Figure 3-2. Page Mode Example
Once the message is received, the READ completes. The applica-
tion reads the screen with a WRITEREAD. The protocol module
issues WRITEREADs to the terminal. After all blocks have been
received, the WRITEREAD is completed as shown in Figure 3-3.
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