Installation guide

Upgrading Memory in Cisco 4000 Series Routers 15
The Cisco 4000 Flash EPROM Card
Caution Correct placement of the Flash EPROMs and PAL is crucial. If improperly positioned, the
new components could be damaged when you power ON the router.
Installing Flash-Memory EPROMs
To install new Flash EPROMs in the eight open sockets (U141 to U148) on the Flash EPROM card
(see Figure 9), align the notch in each EPROM with the notch in an EPROM socket. Insert the Flash
EPROM into the sockets, being careful not to bend any pins. To straighten a bent pin, use needlenose
pliers.
All Flash EPROM sockets should be filled.
Figure 9 Original Cisco 4000 Flash EPROM Card
Replacing the Flash EPROM Card PAL
Follow these steps to replace the PAL at location U2 in Figure 9:
Step 1 Using an IC extraction tool or small flat-blade screwdriver, gently lift the existing PAL out
of its socket, being careful not to damage the underlying printed circuit card.
Step 2 Align the notch in the replacement PAL with the notch in the PAL socket. Insert the PAL
into the socket, being careful not to bend any pins. To straighten a bent pin, use needlenose
pliers.
Flash Jumper Settings
To enable or disable writing a new version of the Cisco IOS to Flash EPROM, set the jumper shown
at the upper left of Figure 9. To allow software update (the factory-set default), place the jumper on
the left two pins. To prevent software update, place the jumper on the right two pins.
To replace the component tray in the chassis shell, continue with the section “Replacing the
Component Tray” later in this document.
Software update
ALLOWED
INHIBITED
U41 U42 U43 U44
U141 U142 U143 U144
U45 U46 U47 U48
U145 U146 U147 U148
U2
H1049a
DC/DC
converter
Card-mounting
screw location
W1
Software update jumper
Card-mounting
screw location
PAL