2. Transmission control procedure matrix
1) Down-loading matrix for the host
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.
—
—
Time-up: One second after sending of ID ENQ.
Four seconds after sending of text.
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