Sharp ER-A440, Service Manual

Page: 24 / 95

2) Up-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 EOT and goes to 3.
NAK — —
Resends the text and then goes to 2.
If the host has resent the text two times, it 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 goes to 0.
(ERROR END) Resends the text and then goes to 2.
If the host has resent the text two times, it 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.
STATE After sending EOT After sending ACK After sending NAK
EVENT 3 4 5
ENQ
Sends ACK and goes to 4. After the host has received ENQ, resends ACK and goes to
4.
After the host has received TEXT, ignores the ENQ.
—
ACK — — —
NAK — — —
EOT
The host goes to 0
(ERROR END) After the host has received TEXT, goes to 0.
(Normal end)
After the host has received ENQ, goes to 0.(ERROR END) The host goes to 0.
(ERROR END)
TEXT —
The host checks the text block, if the block is correct, the
host sends ACK and goes to 4.
If it is not correct, the host sends NAK and goes to 5.
If transmission cannot be continued, the host sends EOT
and goes to 0. The host checks the checks the text block, if the block is
correct, the host sends ACK and goes to 4.
If it is not correct, the host sends NAK and goes to 5.
If transmission cannot be continued, the host sends EOT
and goes to 0.
(ERROR END)
TIME-UP
Resends EOT and goes to 3.
If the host has resent the EOT two times, it goes to 0.
(ERROR END) The host goes to 0.
(ERROR END)
Time-up is 7 seconds The host goes to 0.
(ERROR END)
Time-up is 7 seconds
KEY ENTRY — — —
Time-up: Two second after sending of EOT.
– 8 –