PC IEEE Reference
Technical Details.
The PC IEEE board is capable of a maximum data transfer
rate of 250K bytes/second. The actual data transfer rate is
dependent on the PC’s clock rate. On an 10MHz PC AT or 286
XT the maximum data transfer rate is 200k bytes per second, on
a 4.77MHz PC the maximum data transfer rate is 20K bytes per
second. Of course, the data is actually transmitted at the speed
of the SLOWEST addressed listener or talker. The positive 3
wire handshake ensures that data is transmitted correctly and
without loss.
The IEEE-488 Standard defines the following cabling
restrictions.
1).
Not more than 20 metres between the most distantly
separated devices.
2).
A maximum of 15 devices resident on the bus at the same
time.
The PC IEEE Subsets Supported.
_____________________________
The IEEE-488 standard specifies various allowable subsets
of interface functions. The actual codes supported by the PC
IEEE board is shown below.
Figure 3-1. PC IEEE Board Interface Capability.
__________________________________________
CODE
CAPABILITY
DESCRIPTION
____
__________
___________
SH1
Source Handshake.
Complete capability.
AH1
Acceptor Handshake.
Complete capability.
T7
Talker Function.
Basic Talker,
Extended Talker and Talk Only Mode,
TE7
Extended Talker.
Unaddress if MLA.
L3
Listener Function
Basic Listener, Extended Listener, and
Listen Only Mode,
LE3
Extended Listener
Unaddress if MTA.
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Chapter 3
