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Cisco 819 Integrated Services Router Hardware Installation Guide
OL-23125-02
Chapter 1      Product Overview
  Hardware Features
Memory
The Cisco 819HG and Cisco 819G ISRs uses non-upgradable flash memory and main memory. The 
onboard flash memory contains the Cisco IOS software image and the boot flash contains the ROMMON 
boot code. 
Table 1-8 lists the memory requirements for Cisco 819 ISRs.
SIM Green / Yellow (one 
green blink followed by 
two yellow blinks)
SIM in slot 0 is active, SIM in slot 1 is not.
Yellow / Green (one 
yellow blink followed 
by two green blinks)
SIM in slot 1 is active, SIM in slot 0 is not.
Off / Green (two green 
blinks and then a pause)
No SIM in slot 0, SIM present in slot 1.
Green / Off (Slow single 
green blink and then a 
pause)
SIM present in slot 0, no SIM in slot 1.
Off / Off No SIM present in either slots.
3G/4G Green (one blink and 
then a pause)
For 1xRTT, EGPRS, or GPRS service.
Green (two blinks and 
then a pause)
For EVDO, EVDO/1xRTT, or UMTS service.
Green (three blinks and 
then a pause)
For EVDO/1xRTT RevA, HSPA, or HSUPA/HSDPA 
service.
Green (four blinks and 
then a pause)
For HSPA+ service.
Green (Solid) For 4G/LTE service.
Off No Service.
Table 1-7 4G LTE LED Descriptions (continued)
LED Color Description
Ta b l e  1-8 Memory Requirements for Cisco 819 ISRs
Memory Requirements
Cisco 819HG 
Cisco 819G 
(with 3G)
Cisco 819HGW 
Cisco 819HWD 
(with WiFi)
Cisco 819HG-4G 
Cisco 819G-4G 
(with 4G LTE)
256 Compact Flash support in 
IDE mode (internal)
Yes — —
1 GB Compact Flash support in 
IDE mode (internal)
— Yes Yes
512 MB DRAM  Yes — —
1 GB DRAM  — Yes Yes