
6. PROTOCOL B B-63322EN-1/01
-46-
(1) The remote buffer transmits the DC1 code.
(2) Upon receiving the DC1 code, the host computer shall start
transmitting data to the remote buffer.
(3) Once the amount of free space in the remote buffer falls below
the specified value, the remote buffer transmits the DC3 code.
(4) Upon receiving the DC3 code, the host computer shall stop
transmitting data to the remote buffer.
(5) Once the amount of data in the remote buffer falls below the
specified value, the remote buffer transmits the DC1 code to
request that the host computer restart data transmission.
(6) Upon receiving the DC1 code, the host computer shall restart
data transmission, picking up from the data immediately after
that transmitted last.
(7) When the CNC has been reset or an alarm has been issued in the
CNC, the remote buffer transmits, to the host computer, the DC3
code, followed by the SYN code (for reset) or NAK code (for an
alarm). Thus, data reading is terminated.
(8) The host computer shall stop data transmission.
<When the remote buffer is transmitting data (punch-out)>
(Fig. A)
Reset or alarm
(5)
DC2
If a CNC reset or CNC alarm occurs during
this period, DC4
, SYN, or NAK is not
transmitted.
ER (output)
RS (output)
SD (output)
DR (input)
CS (input)
DC4
SYN or
NAK
(2)
(1)
(3)
(4)
ON
ON