docs: clarify setting up appliance model
Change-Id: Ia7abf8bc098a84c97585715afb782be0eadf8dc0
diff --git a/README.md b/README.md
index 20acccb..a8c8de8 100644
--- a/README.md
+++ b/README.md
@@ -90,14 +90,31 @@
The light changes to solid yellow in later phases of the flashing process.
Once everything is done, the status LED shows a solid white light and the system reboots automatically.
-Turn off power, remove the USB flash, re-jumper the board (`0 0 1 1 1`), power-cycle, and configure MAC addresses and system type at the U-Boot prompt.
+Turn off power, remove the USB flash, re-jumper the board (`0 0 1 1 1`), power-cycle, and configure MAC addresses at the U-Boot prompt.
The MAC addresses are found on the label at the front panel.
```
=> setenv eth1addr 00:11:17:01:XX:XX
=> setenv eth2addr 00:11:17:01:XX:YY
=> setenv eth3addr 00:11:17:01:XX:ZZ
-=> setenv czechlight sdn-roadm-line
+```
+
+Also set up the system type:
+
+| Model | `czechlight` variable value |
+|-------|-----------------------------|
+| ROADM Line Degree | `sdn-roadm-line-g2` |
+| WSS Add/Drop | `sdn-roadm-add-drop-g2` |
+| Hi-resolution Add/Drop | `sdn-roadm-hires-add-drop-g2` |
+| Coherent Add/Drop | `sdn-roadm-coherent-a-d-g2` |
+| Inline EDFA Amplifier | `sdn-inline-g2` |
+
+Some prototypes have deprecated PCBs (blue).
+On these, skip the `-g2` suffix.
+All red PCBs are `-g2`.
+
+```
+=> setenv czechlight sdn-roadm-line-g2
=> saveenv
Saving Environment to MMC... Writing to redundant MMC(0)... OK
=> boot