Delta Tau Universal PMAC Lite, Справочник по аппаратуре

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Universal PMAC Lite
Jumpers Setup Summary 11
Board Reset/Save Jumpers
E39: Reset-From-Bus Enable – Putting this jumper ON ties the ISA-bus reset line to the PMAC Lite
reset line so that a bus reset will automatically reset the PMAC. However, if this jumper is ON and the
PMAC Lite is not installed in an ISA bus, the PMAC will be held permanently in its reset state and will
not operate.
E50: Flash-Save Enable/Disable Control – If E50 is ON (default), the active software configuration of
the PMAC can be stored to non-volatile flash memory with the
SAVE
command. If the jumper on E50 is
removed, this
SAVE
function is disabled, and the contents of the flash memory cannot be changed.
E51: Re-Initialization on Reset Control – If E51 is OFF (default), PMAC executes a normal reset,
loading active memory from the last saved configuration in non-volatile flash memory. If E51 is ON,
PMAC re-initializes on reset, loading active memory with the factory default values.
E93-E94: Reset from Bus by Software Enable – These jumpers permits hardware resets of the PMAC
(which work even if the watchdog timer has tripped) through software operations from the PC. If E93 is
ON, the PMAC PC powers up locked in the reset state. It can be put in the operational state by the PC
writing a value of 40hex to {base a 12}; it can be put back in the reset state by the PC writing a
value of 40hex to {base a 10}. If E94 is ON, the PMAC PC powers up in operational mode. It
can be put in reset mode by the PC writing a value of 40hex to {base a 12}; it can be put back in
operational mode by the PC writing a value of 40hex to {base a 10}.
E103: Watchdog Timer Disable – If E103 is installed the watchdog safety function will be disabled.
This jumper is for testing purposes only.
E106: Power-Up/Reset Load Source – If E106 is installed when the PMAC Lite executes its reset cycle,
PMAC enters a special re-initialization mode that permits the downloading of new firmware through
either the serial port or the bus port. In this bootstrap mode, there are very few command options. PMAC
will respond to any of the status-bit query commands (
?
,
??
, or
???
) with the response Bootstrap
PROM. This permits the host to know whether PMAC is in this mode or not. PMAC will respond to the
VERSION query command with the number of the bootstrap firmware (e.g. 1.01), which will probably be
different than the operational firmware version. To bypass the download operation in this mode, send a
<CONTROL-R> character to PMAC. This puts PMAC in the normal operational mode with the existing
firmware. Factory default values for I-variables, conversion table settings, and bus addresses for DPRAM
are copied from the firmware section of flash memory into active memory. The saved values of these
values are not used, but they are still kept in the user section of flash memory.
Note:
Before attempting to upgrade PMAC operational firmware, make sure all of
PMAC’s configuration has been stored to disk. If the new firmware provides a
different user memory map, PMAC will clear memory on power-up after new
firmware has been loaded. Even if this is not the case, the easiest way to establish
a new firmware checksum reference value is to send the $$$*** command, which
clears the buffers. For any change in the operational firmware, the compiled PLCs
will have to be re-compiled with the List Link file for the new firmware version. It
is important to delete all compiled PLCs (Delete PLCC n) before attempting to
change the operational firmware version. Compiled PLC programs running under
a firmware version other than that which they were compiled for can have
unpredictable consequences.