Sharp XE-A201

XE-A201UC
– 4 –
2. TRANSMISSION CONTROL PROCEDURE MATRIX
1) Down-loading matrix for the host
Time-up: One second after sending of ID ENQ.
Four seconds after sending of text.
( 15 ) Sends ACK.
( 17 ) Terminates the operation if EOT is received.
( 12 ) Sends text corresponding
to the job code.
( 14 ) Resends text block if NAK is received.
Resends text up to two times,and
performs error handling if NAK is still
received after the second resending
of text block.
Host Satellite
EOT
Continued from the
preceding page.
Start code Text (FDS) End code
Text (DATA)
Two types of
text block
formats are
available.
NAK
(When an error
occurs)
ACK
Note : For the description of
each data block see section
4 (Text block formats)
( 13 ) Receives text.
Checks the check sum, text length, text data, etc.
And goes to (15) if there is no error in them.
Sends NAK if any error occurs.
( 16 ) Sends the next text if ACK is received,
and sends EOT and terminates the
operation if data transfer is finalized.
STATE Initial After sending ID ENQ After sending text
EVENT 0 1 2
ENQ ...
ACK .
Sends text and goes to 2. Sends text and goes to 2.
Sends EOT and then goes to 0.
(Normal end)
NAK ..
Resends the text and then goes to 2.
If the host has resent the text two times, it
sends EOT and goes to 0.
(ERROR END)
EOT ..
The host goes to 0.
(ERROR END)
TEXT ...
TIME-UP .
Resends ID ENQ and then goes to 1.
If the host has resent ID ENQ two times, it
sends EOT and goes to 0.
(ERROR END)
Resends the text and then goes to 2.
If the host has resent the text two times, it
sends EOT and goes to 0.
(ERROR END)
KEY ENTRY Sends ID ENQ and goes to 1. ..