Black Box PCW22A-R4, PCW22A-R3 manual Nak

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CHAPTER 4: Operation

Data Flow — A/S-2G to Synchronous Device

Bisynchronous Device

A/S-2G Converter

Asynchronous Device

If A/S-2G buffer is nearly full when asynchronous device is transmitting:

				X-OFF		Holds up transmission while
				X-OFF		Holds up transmission while
						buffer clears DC3 (ASCII 13
						Hex) or drop DTR CTS or
						user-specified lead
ACK 1				Send block C		Frees up buffer space.
				Send block C

						(Echo CR LF)



				X-ON		Allow resumption of
				X-ON		Allow resumption of
						transmission DC1 (ASCII 11
						Hex) or raise DTR

Complete block D

If data not properly received by synchronous device or

synchronous device has no WAK capability and buffer is full:

Send block D

NAK

Negative Acknowledgment

AA AA 32 32 32 32 3D FF FF

Resend block D

ACK 0

If synchronous device has WAK capability and buffer is full:

Send block E

(Echo all but CR LF)

Send block E

2-second interval

WAK

AA AA 32 32 32 32 6B FF FF

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Contents Protocol Converter FCC Statement Protocol Converter A/S-2G Table of Contents Synchronous Device to Asynchronous Device Specifications RXCIntroduction Data Flow Control InstallationUnpacking and Inspection 2 SW2 Switch #4 on = SELF-DIAGNOSTICSReconfigure Switch Mode Reset OptionsData Terminal Ready DTR Signal Options 5 RS-232 PASS-THROUGH OptionsModem or DIRECT-TO-TERMINAL Connection Clear to Send CTS Signal OptionsBaud Rate Options Cable Requirement Preparing the A/S-2G for Connection to a Synchronous DeviceCarrier Options External or Internal Clocking Option Command PASS-THRU Operation Asynchronous Device to Synchronous DeviceUSE of Carriage Return a 2770/2780 Mode Flow ControlLine Turnaround Presentation of Data from A/S-2G to Synchronous DeviceVerification of Data Reception Data Flow A/S-2G to Synchronous Device NAK Echo CR LF Send block F Echo all but CR LF Data Flow A/S-2G to Synchronous Device Synchronous Device to Asynchronous Device Synchronous Input Data FormatEbcdic characters stripped Data Flow A/S-2G to Asynchronous Device Operation EOT Conversions and Connections Transparency Mode of OperationInstalling or Replacing Proms RS-232 Cable Chart GNDCode Conversions Special Conversions Printed Circuit Board Layout Printed Board Circuit LayoutPark Drive Lawrence, PA