HP 8920B, Programmer'S Manual

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Chapter 7, IBASIC Controller
Interfacing to the IBASIC Controller using Serial Ports
Receive and Transmit Pacing
When receiving characters into the
IBASIC Command Line
field, the Test Set’s
microprocessor responds to each entry and no buffering is required. Therefore,
when using your PC or terminal to send characters to the
IBASIC Command
Line
field, it is permissible to set
Rcv Pace
and
Xmt Pace
to
None
.
When sending data through the Test Set’s Serial Port to external devices like
printers which may have small input buffers, it is important to set
Rcv Pace
and
Xmt Pace
to
Xon/Xoff
. This allows the printer to stop data transmission from
the Test Set when the printer’s buffer is full and then start it again when the printer
is ready.
The Test Set has a Serial Port input buffer length of 2000 characters with
firmware revision B.01.00 and greater. Buffer size becomes important when
IBASIC programs expect to receive large amounts of data through the Serial Port
with a single ENTER statement.
Table 40 Test Set Serial Port 9 Configuration
Field Available Settings Recommended Setting
Serial In Inst/IBASIC Inst
IBASIC Echo On/Off On
Inst Echo On/Off On
Serial Baud Rate 150, 300, 600, 1200, 2400, 4800,
9600, 19200 9,600
Parity None, Odd, Even, Always 1,
Always 0 None
Data Length 7 bits, 8 bits 8 bits
Stop Length 1 bit, 2 bits 1 bit
Rcv Pace (receive pacing) None, Xon/Xoff Xon/Xoff
Xmt Pace (transmit pacing) None, Xon/Xoff Xon/Xoff