ON-LINE CONFIGURATION
OPERATION
B - 6
I-E96-203C
Elsag Bailey
Process A utom ation
Primary Cycle
for the primary cycle procedure. The step
numbers in this cycle correspond to the states of Figure
This information is provided for status purposes. Follow the
backup cycle procedures to perform on-line configuration,
Table B-3. Primary Cycle
Primary
Backup
Procedure
n
01xx0x0x
z
z
n+1
10xx1x0x
{
5
1. The primary module is actively controlling the process. This represents the
same juncture as Step 4 of the backup cycle.
n+1
01xx0x0x
{
z
n
11xx1x0x
5
5
2. When the shutdown request is received from the backup module (Step 7 of
the backup cycle), the primary module stops executing and removes the bus
clock (BUSCLK).
n+1
01xx0x0x
{
z
n
01xx1x0x
5
5
3. The primary module is now acting as the hot backup (n+1). All old configura-
tion and block output information remains intact from when it is shut down in
Step 2. If the new configuration is not operating as expected, the primary mod-
ule, currently acting as the hot backup (n+1), can take control using the old con-
figuration and block output information (returns to Step 1).
n+1
00xx0x0x
{
{
n
00xx1x0x
5
5
4. Resetting the primary module (n+1), currently acting as the hot backup,
directs it to get a copy of the new configuration (Step 8 of the backup cycle).
n+1
10xx0x0x
z
{
n
00xx0x0x
z
z
5. When the new configuration has been copied, the backup module has com-
pleted its cycle and is now serving as the primary module.
n+1
10xx0x0x
{
z
n
00xx0x0x
z
z
6. After the checkpoint data is complete, the primary module is now serving as
the backup module and is ready to take over the control process with the
updated configuration. The primary cycle is complete. This represents the same
juncture as Step 10 of the backup cycle.
