Siemens Simatic M7-400 Reference Manual page 446

CPUs for M7-400
Power Up with Error Message
If one of the following errors occurs:
• Memory test error
• Hard disk configuration error
• CMOS checksum error,
the INTF LED remains lit as well as the STOP LED. A window appears on the
screen with the relevant error message. The window disappears after
approximately two seconds and the power up continues.
With an incorrect CMOS checksum, the default settings are loaded.
Behavior in the Event of Serious Errors
In the case of serious errors, the power up is stopped. Serious errors include:
• No memory plugged in.
• More than one IF962-VGA interface submodule has been plugged in (INTF LED
lights up).
• The CMOS memory location 15 (0xF) contains an invalid shutdown code during
the warm restart.
These errors prevent screen output since the video unit is not initialized. The
INTF LED lights up.
Ensure that the MEM 478 DRAM memory submodules required for operation are
plugged into the CPU or check to see if more than one IF262-VGA interface
submodule has been plugged into the CPU. If you do not find an error, there must
be an invalid shutdown code. If this is the case, reset the CPU using power off/on.
Warm Restart
After a warm restart of the CPU, the following window appears signaling an
accelerated system power up (see Section 11.4.2 "BIOS Hot Keys").
Figure 11-7
11-18
Warm Restart Window for a CPU
S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07