The Negotiation Phase
219
Byte Mode
The printer and host send data to each other along eight data lines (one bit
per line).
If bidirectional communication is supported by the printer and the host, the
host will take control of the data transfer.
The Negotiation Phase
The negotiation phase determines which operating mode will be used. At this
time, the host and the printer will sense what devices are attached, the
supported signals available, and which mode to use. The selected mode, in
turn, defines the pins on the 1284 connector.
There are 36 pins on the parallel interface. Each one sends a different signal.
Pin 1, for example, can send a Strobe signal or a HostC1k signal, depending
on the mode selected. See Table 9 for the different connector signals.
Signals
Table 9 lists each of the signals associated with the corresponding pins on the
1284 interface. Descriptions of the signals follow.
Table 9. 1284 Signals
Pin
Source of Data
Type of Mode
Compatible
Nibble
Byte
1
Host
nStrobe
HostClk
Host/Clk
2
Host/Printer
Data 1 (LSB)
3
Host/Printer
Data 2
4
Host/Printer
Data 3
5
Host/Printer
Data 4
6
Host/Printer
Data 5
7
Host/Printer
Data 6
8
Host/Printer
Data 7
9
Host/Printer
Data 8 (MSB)
10
Printer
nAck
PtrClk
PtrClk
11
Printer
Busy
PtrBusy
PtrBusy
12
Printer
PError
AckDataReq
AckDataReq
13
Printer
Select
Xflag
Xflag
Summary of Contents for 6400 Series
Page 2: ......
Page 3: ...6400 Line Matrix Printers S544 5640 01 Setup Guide Cabinet and Pedestal Models...
Page 18: ...xviii Safety Notices...
Page 86: ...86 Chapter 2 Test The Printer...
Page 208: ...208 Chapter 4 RibbonMinder Menu...
Page 224: ...224 Chapter 5 IEEE 1284 Parallel Interface...
Page 262: ...262 Appendix B Printing Speed...
Page 268: ...268 Appendix C Compatibility and Limitations...
Page 286: ...286 Appendix D Physical and Logical Unit Types...
Page 315: ......
Page 316: ...Copyright IBM Corp 1998 2002 174585 001A S544 5640 01 54P0515...