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TB007  MISSING CHANNEL + DEV END WITH HYII PRINTERS
 
                J.D.S. MicroProcessing Technical Bulletin             
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Date Written: 08/02/89                   Submitted by: R. Sande     
    Sequence: 1 of 1                           FileID: 4.TB007      
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              MISSING CHANNEL + DEV END WITH HY-II PRINTERS                 
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    This condition is usually caused by incorrectly setting the time    
field on the Hydra-II's TYP1 record. Depending on the level of code     
a printer type device must be specified as PRTR in this field.          
                                                                        
    This time field works in conjunction with an interrupt time-out       
parameter set within the Host Computer's Operating system. If the Hydra
does not send channel and device status within this interrupt time-out    
period specified on the host the error message will result.             
                                                                        
    This condition can be further recognized if it occurs shortly after
the printer runs out of paper or goes off-line for any other reason.     
                                                                        
    Another cause for this type of error might be that the Hydra is     
getting reset by some other unpredictable force. For example: a manual  
reset or interface control check reset, or the unit might possibly      
need an MVS/XA selective reset modification.                            
                                                                        
    The time-out value on the Host Computer is usually set in the system
generation however, you must be careful if the customer is running a     
guest machine. The value should be about 3-5 minutes on the host and    
about 60 seconds on the printer (PRTR = 60 by default). Also check to   
make sure that the customer does have the PRTR in the time field. Using
DFLT will almost always cause an error.                                 
                                                                        
IN THE CASE OF A VM/CMS OPERATING SYSTEM THE USER CAN CHANGE THE    
TIMEOUT VALUE INTERACTIVELY WITHOUT RE-IPL'ING BY USING THE SET MIH     
(MISSING INTERRUPT HANDLER) COMMAND. HAVE THE USER CONSULT HIS OPERATING SYSTEM GUIDES FOR THE CORRECT WINDOW SIZE.