Serial I/O Commreq Commands; Overlapping Commreqs - Emerson PACSystems RX3i User Manual

PACSystems™ RX3i and RSTi-EP CPU Reference Manual
GFK-2222AK
Major Error Code Description
6.2.4

Serial I/O COMMREQ Commands

■
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6.2.5

Overlapping COMMREQs

Some Serial I/O COMMREQs must complete execution before another COMMREQ can be
processed. Others can be left pending while others are executed.
Serial I/O, SNP & RTU Protocols
8 (08h)
9 (09h)
10 (0Ah)
11 (0Bh)
The following COMMREQs are used to implement Serial I/O:
Local COMMREQs - do not receive or transmit data through the serial port.
Initialize Port (4300)
❑
Set Up Input Buffer (4301)
❑
Flush Input buffer (4302)
❑
Read port status (4303)
❑
Write port control (4304)
❑
Cancel Operation (4399)
❑
Remote COMMREQs - receive and/or transmit data through the serial port.
Autodial (4400)
❑
Write bytes (4401)
❑
Read bytes (4402)
❑
Read String (4403)
❑
Modem responded with NO DIALTONE. Modem is
unable to complete the requested connection. Check
the modem connections and the telephone line.
Modem responded with ERROR. Modem is unable to
complete the requested command. Check the modem
command string and modem.
Modem responded with RING, indicating that the
modem is being called by another modem. Modem is
unable to complete the requested command. Retry the
modem command later.
Unknown response received from the modem. Modem
unable to complete the request. Check the modem
command string and modem. Response should be
CONNECT or OK.
Section 6
October 2019
144