Measurement Computing Personal488 rev.3.0 For DOS & Windows 3.Xi - Manual (Page 305)

15A. Driver488/DRV Commands III. COMMAND REFERENCES - 15. Command References
III-290 Personal488 User’s Manual, Rev. 3.0
EXAMPLES PRINT#1,"ENTER16#100 BUFFER
&H2000:0"
Read 100 characters into memory at &H20000.
PRINT#1, “ENTER16#100 BUFFER
&H20100 EOI”
Read 100 characters, or until EOI is detected into
memory at absolute location 20100.
PRINT#1,"BUFFERED"
INPUT#2,N
PRINT#1, “ENTER16#100 BUFFER
262144 CONTINUE”
Read 100 characters as before, but allow the
program to continue while the transfer is
taking place.
PRINT#1, “WAIT” Wait until the transfer has completed.
PRINT#1, “ENTER16#100 BUFFER
262144 CONTINUE EOI”
Read 100 characters as before, but stop if the EOI
(end or identify) signal is encountered.
PRINT#1,"WAIT" Wait until the transfer has completed.
PRINT#1,"BUFFERED”
INPUT#2,NBUFFERED Get the number of characters actually read.
The ENTER #count BUFFER command reads data from the I/O adapter into a user-supplied memory
region. If a device address (with optional secondary address) or name is specified, Driver488 is
addressed to Listen, and that device is addressed to Talk. If no address is specified, Driver488 must
already be configured to receive data, either as a result of an immediately preceding
ENTER command,
or as a result of one of the SEND commands.
The character count count must be specified and is the maximum number of characters that is
transferred. ENTER #count BUFFER does not detect the input terminator unless it is explicitly
specified in the command. Otherwise the specified number of characters is received. The number of
characters actually received can be checked with the
BUFFERED command. The terminator characters,
if received, are placed into the memory buffer.
If CONTINUE is specified, Driver488 returns control to the user’s program as soon as possible, without
waiting for the transfer to be completed. It does, however, wait for the first byte to check for time-out
unless a time-out value of
0 had been specified by a TIMEOUT command. Because of hardware
limitations, the CONTINUE may not return until a substantial portion of the transfer is complete, if
configured for no interrupts.
CONTINUE transfers are not finished until Driver488 has had an opportunity to “clean up” and complete
the transfer. This “clean up” is usually automatic: Driver488 implicitly performs a WAIT command
before performing any bus command. The program can itself use the WAIT command to guarantee that
the transfer is complete.
All characters read, including the bus terminator, if any, are placed in the memory buffer; no terminator
translation is performed. The
EOL IN terminator is not put into the memory buffer.
ENTER #count BUFFER (Peripheral mode)
SYNTAX ENTER[;] #count[;]BUFFERbuf-addr[CONTINUE][term][term][EOI]
count is the number of characters to ENTER .
buf-addr is the memory buffer address.
CONTINUE specifies asynchronous transmission.
term and EOI override the normal bus input terminators.
RESPONSE None, returned data is placed directly into the specified
memory buffer.
MODE *CA
BUS STATES Determined by the Controller.
SEE ALSO OUTPUT, TERM, EOL, BUFFERED
EXAMLES See next page.