GE PACSystems RX7i, Справочное руководство, Страница: 227 / 317

Chapter 6. Serial I/O, SNP & RTU Protocols
216 PACSystems* RX7i, RX3i and RSTi-EP CPU Reference Manual GFK-2222AD
Port Status Word Meanings
Bit Name Definition Status Meaning
15 RP
Read In
progress
Set Read Bytes or Read String invoked
Cleared Previous Read bytes or String has timed out, been canceled, or finished
14 RS
Read
Success
Set Read Bytes or Read String has successfully completed
Cleared New Read Bytes or Read String invoked
13 RT
Read Time-
out
Set Receive timeout occurred during Read Bytes or Read String
Cleared New Read Bytes or Read String invoked
12 WP
Write In
progress
Set New Write Bytes invoked
Cleared
Previously-invoked Write Bytes has timed out, been canceled, or
finished
11 WS
Write
Success
Set Previously-invoked Write Bytes has successfully completed
Cleared New Write Bytes invoked
10 WT
Write
Time-out
Set Transmit timeout occurred during Write Bytes
Cleared New Write Bytes invoked
9 CA
Character
Available
Set Unread characters are in the buffer
Cleared No unread characters in the buffer
8 OF
Overflow
error
Set Overflow error occurred on the serial port or internal buffer
Cleared Read Port Status invoked
7 FE
Framing
Error
Set Framing error occurred on the serial port
Cleared Read Port Status invoked
6 PE
Parity
Error
Set Parity error occurred on the serial port
Cleared Read Port Status invoked
5 CTS
Clear to
Send
Set Clear to Send signal is active
Cleared Clear to Send signal is not active
4 DSR
Data Set
Ready
Set Data Set Ready signal is active
Cleared Data Set Ready signal is not active
3 RI
Ring
Indicator
Set Ring Indicator signal is active
Cleared Ring Indicator signal is not active
2 DCD
Data
Carrier
Detect Set Data Carrier Detect signal is active
Cleared Data Carrier Detect signal is not active
1-0 n/a Not used These bits are always set to 0
Operating Notes
For reference, see the tables under Serial Port Pin Assignments in Chapter 5.
Support for the DSR status bit is provided for COM1 only, on all RX7i and RX3i models (except
CPE302/CPE305), in Rel. 7.16 and later releases.
Support for the RP and DCD status bits is provided only for COM1 on the CPE310, in Rel. 7.16 and later
releases.