106 C4 Manual Rev 7.5.2
If you are having no success with bus communications, check to be certain that
the correct bus (EIA-232 or GPIB IEEE-488) is selected using setup parameter F2.
SI (Immediate Mode) or the default SP (Program Mode) are typically issued at the
beginning of a program sequence. However they may be issued at any point. If
the C4 receives a SI command and there is a command executing and/or
commands in the command buffer, the executing command is interrupted and the
command buffer is cleared.
The Aux/Power ON (TO) and Aux/Power OFF (TF) commands control the
auxiliary power control port. This port is normally used to control power to the
chamber or platform or an optional device. It is not necessary to use these
commands to enable and disable temperature control.
EIA-232 Problems
EIA-232 issues are usually communications interface related. The C4 is
configured as DCE (Data Communications Equipment). Therefore, it is not
appropriate to use a crossover or “null modem” cable. Use a straight-through
cable that does not have pins 2 and 3 reversed. The C4 does no hardware or
software handshaking. DTR and CTS are constantly asserted by the C4 for
compatibility with devices that need these signals. Hardware handshaking from
the controlling device is ignored. Software handshaking will be parsed as data by
the C4 and will reliably result in failure.
GPIB IEEE-488 Problems
C4 status requests are available either via the manual RS (read status) command
or by enabling SRQ with the ES command and then using serial poll to obtain the
status byte. The serial poll method will only return the status byte after SRQ is
enabled with an ES command.
9.7.8 Firmware Upload Problems
Firmware upload is very straight forward and has no options except for the user to
select a COM port on the PC. If the upload never starts after the PC program is
started, try turning the controller off and then back on and reinvoking rS LOAd
mode. Depending on the behavior of the COM ports on the two devices, some
experimentation may be in order as to which device needs to be brought up first.
If your uploads appear to run properly and the upload software indicates a
successful result, yet the system will not run, you should try the load again. It is