The Barr Communication Scope displays detailed information about communication between the PC and mainframe. The Communication Scope can display the last 40 communications events.
When you begin communications on the BARR/RJE Operation screen, BARR/RJE tries to connect with the mainframe and then log on. For a dial-up connection, you can see dial-up characters on the Communication Scope and logon error messages on the console. Dial-up scope characters display in white and logon error messages display in red.
After BARR/RJE connects with the mainframe, the remote goes into Normal Response Mode (Snrm on the Communication Scope). Then the mainframe and remote exchange frames of information.
Colors indicate whether the activity comes from the PC or
the mainframe. When BARR/RJE sends a message to the mainframe, green characters appear. When BARR/RJE receives
a message, magenta characters
appear. On a monochrome display and in this manual, the sent message appears
in normal text and the received message appears in reverse video.
This chapter groups scope characters by the type of communications activity they represent and then by the mainframe connection type. The screen displays different scope characters for SDLC, 802.2, and Coax connections.
X.25 connection: Uses the same Communication Scope
characters as SDLC connections.
Async connection: A numeric return code displays on
the Communication Scope when the PC connects to the mainframe, but the
return code meaning depends on the modem type. Your modem manual explains
asynchronous return codes.
To follow BARR/RJE’s progress while it tries to connect to the mainframe, watch the Communication Scope. Dial-up scope characters (see Table 22-1) display in white. For instance, you can see if BARR/RJE dialed the phone number, if there was no answer, or if the line was busy.
Table 22-1. Dial-Up Scope Characters
|
Character |
Description |
|
A |
Answer tone. Host modem sent answer tone to remote. |
|
B |
Busy. Host modem is busy. |
|
D |
Dialing. In the process of dialing. |
|
N |
No answer. No answer tone has been detected. Modem redials. |
|
R |
Ringing. Host modem is ringing. |
Dial-up scope characters usually appear in sequences on your Communication Scope. For example:
DB
– Dialing, Busy
DRA – Dialing, Ringing, Answer
DRND – Dialing, Ringing, No answer, Redialing
After the PC connects to the mainframe, the remote goes into Normal Response Mode (Snrm on the Communication Scope) and data communications begin. Characters on the Communication Scope reflect activity between the PC and mainframe.
Tables 22-2 and 22-3 list Communication Scope characters for SDLC and X.25 connections.
Table 22-2. SDLC and X.25 Scope Characters
|
Characters |
Description |
Notes |
|
0-7 |
Information frame |
Frame number. |
|
Disc |
Disconnect |
Host sends Disc to force remote into Normal Disconnect Mode. |
|
Dm |
Disconnected mode |
When the remote is in Normal Disconnect Mode and the host sends frames the remote cannot process, the remote sends Dm to request an Snrm. Should only occur when program restarts. |
|
Frmr |
Frame reject |
A frame was not formatted correctly. Should never occur. |
|
Rej |
Reject |
Sender of the Rej has received an information frame out of sequence and is asking for it to be sent again. Only used for full-duplex communications. |
|
Rnr |
Receive not ready |
Sender is unable to receive any information frames. Try increasing Memory allocated for buffers to 400,000. See section 18.6, Trace and Memory Options, for more information. |
|
Rr |
Receive ready |
Sender is ready to receive information frames. During idle periods, Rr messages bounce back and forth. Extra Rr messages could indicate that the Barr software is set for full duplex (DATMODE=FULL), but the host is set for half duplex (DATMODE=HALF). See Chapter 2 of the Host Definition Guide for more information about DATMODE. |
|
Sabm |
Set asynchronous balanced mode |
Sent by BARR/RJE X.25 connection to initialize the link to the X.25 network. Applies only to X.25 connections. |
|
Snre |
Set normal response mode extended |
Host sends Snre instead of Snrm for modulo 128 sequence numbering. See the modulo 128 discussion later in this section. |
|
Snrm |
Set normal response mode |
Host sends Snrm to remote setting Normal Response Mode. |
|
Ua |
Unnumbered acknowledgment |
Positive response to an SDLC mode-setting command such as Snrm. |
|
Undf |
Undefined |
Unrecognized frame received. Should never occur. |
|
Xid |
Exchange identification |
Host sends Xid to request remote identification. |
|
Xidr |
Exchange identification response |
Remote sends identification data IDBLK and IDNUM, which define a switched PU in a VTAM library. |
|
! |
Illegal |
When this follows a received frame (for example, Rr!), the frame is not formatted correctly or is illegal in this mode. Should only occur when the program restarts. |
Table 22-3. SDLC and X.25 Scope Characters Indicating Errors
|
Character |
Description |
Notes |
|
A |
Abort |
Frame ended with 1111111 (seven or more consecutive 1s), not with a frame character. |
|
C |
CTS failure |
Clear-To-Send signal is not available from modem. |
|
E |
Error with Cyclical Redundancy Check (CRC) of frame |
CRC computed on bits in frame received does not agree with CRC value of frame sent. For example, noise on the telephone line could cause a bit to be lost in the frame. The SDLC protocol causes the frame to be re-sent. |
|
F |
Send failure |
Transmit clock signal is probably not available from modem. |
|
N |
Non-productive receive |
None of the frames received in the last 5 seconds match the SDLC address or they were random noise frames. |
|
Q |
Queue overflow |
More frames received than buffers available. Try increasing Memory allocated for buffers to 400,000. See Trace and Memory Options in Chapter 18 for more information. |
|
T |
Timeout |
No answer for 3 seconds. Numerous timeouts could indicate that the Barr software is set for DATMODE=FULL but the host is set for DATMODE=HALF. See Chapter 2 of the Host Definition Guide for more information about DATMODE. |
|
V |
Overrun of receive buffer |
Ending frame character was not found before buffer was filled. |
|
X |
Equipment error |
Send underrun or receive overrun. Usually caused by LAN or hard disk turning off interrupts. Try changing the Interrupt request in the software. (For older adapters, such as the BARR/3, try setting Use DMA for communications to Yes. Your Barr adapter manual discusses this option.) If this error is related to typing on the keyboard, use the TSR program BIOS_KEY included with the Barr reference files. BIOS_KEY briefly turns off interrupts. |
DRAXidXidrSnrmUaRrRr00
Normal dial-up sequence.
DRAEETTTTTT
Modem answered but NRZI probably needs to be changed. See Chapter 2 of the Host Definition Guide for more information.
DRAXidXidrTTTTT
The Xid failed. Probably IDBLK and IDNUM are not correct. See Chapter 2 of the Host Definition Guide for more information.
RrRrRrRrRrRr
Line is idle. No information frames are being exchanged.
0123456RrRr7012345RrRr
Host is sending information. Remote is idle.
01234Rr4567012Rr5670123Rr
Both host and remote are sending information.
012E456RrRr3456701RrRr
Frame 3 received in error. Communication resumed at frame 3.
SnrmUaSnrmUa
BARR/RJE can hear the host but the host cannot hear BARR/RJE. Try setting Constant RTS to Yes. See section 18.4, Modem and Line Control, for more information.
TTTTT
Try changing NRZI and then check your modem connection. See Chapter 2 of the Host Definition Guide for more information.
The Communication Scope tells you if the mainframe is operating in modulo 8 or modulo 128 mode. At logon, the host sends Snrm for a modulo 8 link or Snre for a modulo 128 link.
Even if you set the mainframe parameters to use modulo 128 and you see an Snre on the Communication Scope, the software might send only seven frames at a time (as if it was in modulo 8 mode) if the PC does not have enough memory. A Q or an Rnr on the Communication Scope indicates low memory. You also might see the More memory needed for buffers message on the BARR/RJE console. Try increasing the Memory allocated for buffers option by MAXOUT * 1024. As MAXOUT increases, so do the requirements for buffers. See Chapter 2 of the Host Definition Guide for more information.
After the PC connects to the mainframe, the remote goes into Normal Response Mode (Snrm on the Communication Scope) and data communications begin. Characters on the Communication Scope reflect activity between the PC and mainframe.
Table 22-4 lists Communication Scope characters for 802.2 connections.
Table 22-4. 802.2 Scope Characters
|
Characters |
Description |
Notes |
|
0-7 |
Information frame |
Frame number of the information frame. |
|
A |
Open |
Open the token ring adapter. Only performed if not already opened. |
|
C |
Connection established |
802.2 connection established. |
|
Enn |
Error status returned from PC token ring adapter |
The codes (nn) are defined
in Adapter Check Reason Codes in the Local
Area Network Technical Reference (IBM SC30-3383-2). |
|
Frr |
Frame reject received |
A frame reject has been received. The five-byte reject information is included in the scope. This indicates a link level protocol violation was detected by the remote link station. One possible violation is an incompatible frame size between partners. Check that MAXDATA set in BARR/RJE matches MAXDATA set for the mainframe (or controller, if attached to a 3174 Controller). See Chapter 2 of the Host Definition Guide for more information about MAXDATA. |
|
Frs |
Frame reject sent |
A frame reject has been sent. The five-byte reject information is included in the scope. This indicates a link level protocol violation was detected by the remote link station. One possible violation is an incompatible frame size between partners. Check that MAXDATA set in BARR/RJE matches MAXDATA set for the mainframe (or controller, if attached to a 3174 Controller). See Chapter 2 of the Host Definition Guide for more information about MAXDATA. |
|
I |
Initialize |
Initialize the token ring adapter. Performed only if not already initialized. |
|
L |
Open link station |
Allocate a link station before making a connection when in host mode. |
|
Pc |
Computer error |
Indicates hardware error. |
|
Ring |
Ring error |
Adapter has detected a token ring error. |
|
Rnr |
Receive not ready |
Local station or remote partner has entered a local busy state, which is caused by a low buffer condition. |
|
Rr |
Receive ready |
Local busy state has cleared. |
|
S |
Open SAP |
Allocating and opening a Service Access Point. |
|
Sabme |
Set Asynchronous Balanced Mode Extended |
Request for connection was received from the host. |
|
Stat |
Status request |
E09 and E0C are valid normal responses. Other status might indicate adapter errors. |
|
T |
Timeout |
No response from the host adapter. |
|
Undf |
Undefined |
An unrecognized frame was received. Should never occur. |
|
Xid |
Exchange identification |
After the remote sends Xid to tell the host that it wants to make a connection, host sends Xid to request identification of remote. |
|
Xidr |
Exchange identification response |
Remote sends identification data IDBLK and IDNUM. This data defines a switched PU in a VTAM library. |
|
Xidrz |
Exchange identification response |
Controller responds with routing information. |
|
Xidz |
Exchange identification |
Remote sends Xidz to host Controller Address to request routing information. |
StatIASXidzXidrzXidXidXidrC00
Normal connection if the adapter was not previously opened. IA indicates initialization and open.
StatSXidzXidrzXidXidXidrC00
Normal connection if the adapter was opened by other software (for example, network software).
StatSXidzE22
The host Controller Address entered in the Communication Link cannot be located on the ring.
StatSE46
Resources are not available to open a SAP. When the adapter was first opened by LAN software, not enough memory was reserved.
StatIASXidzXidzXidz
No response from the host. Check LOCADD under Communication Link for the address of the host adapter; otherwise, check for a route problem.
StatIASXidzXidrzXid
If you are connecting to a 3174, check Q940 in the controller setup to ensure the Barr device is defined.
After the PC connects to the mainframe, the remote goes into Normal Response Mode (Snrm on the Communication Scope) and data communications begin. Characters on the Communication Scope reflect activity between the PC and the mainframe.
Table 22-5 lists Communication Scope characters for Coax connections.
Table 22-5. Coax Scope Characters
|
Characters |
Description |
Notes |
|
+nnn |
Online |
LU nnn is online to the host. |
|
-nnn |
Offline |
LU nnn is offline to the host. |
|
0-7 |
Information frame |
Frame number of the information frame. |
|
B |
Bind |
Requests communications controller to read a BIND or UNBIND response via a synchronous write. |
|
Coax |
Coax protocol |
Link-level protocol being used. |
|
E |
Error condition |
Condition error received from communications controller. |
|
I |
Initialization complete |
Adapter loaded with microcode and initialized. |
|
Porn |
Power-on reset |
Power-on reset for port n sent to communications controller. |
|
Pornr |
Power-on reset response |
Power-on reset from port n acknowledged by communications controller. |
|
T |
Timeout |
No commands received from communications controller in the last second. |
CoaxIPor0Por0r+002+003+004001122
Normal communication scope sequence.
CoaxIPor0Por0r+002+003+004-002-003-004