diff --git a/RTL8218B.md b/RTL8218B.md
index 01ce952f..eaa9adb0 100644
--- a/RTL8218B.md
+++ b/RTL8218B.md
@@ -9,7 +9,7 @@ Page | Register | Bits | Feature | Documentation
 **Page** | **Register** | **Bits** | **unknown** | 
 0xa42 | 0x14 | 07:07 | 500M_EEE_ABILITY
 
-These additional/internal registers are organized in pages of 8. Each page knows registers 0x10-0x17
+These additional/internal registers are organized in pages of 8. Each page knows registers 0x10-0x17. Their "absoulte" address can be calucalted by the formula page * 8 + (register - 16)
 
 Page | Register | Bits | Feature | Documentation
 --- | --- | --- | --- | ---
@@ -75,6 +75,8 @@ Page | Register | Bits | Feature | Documentation
 0x404 | 0x17 | 08:08 | CFG_MARK_TXSCR_ERR | 
 0x404 | 0x17 | 07:04 | BYP_START | 
 0x404 | 0x17 | 03:00 | BYP_END | 
+**Page** | **Register** | **Bits** | **MAC SerDes 0 - page unknown** | **Absolute 0x2120**
+0x40c | 0x11 | 15:00 | | This is some unknown PLL register - write 0x4000 to diable ring PLL
 **Page** | **Register** | **Bits** | **MAC SerDes 1 - page 0** | **Absolute 0x2120**
 0x424 | 0x10 | 15:15 | DIS_RENWAY | 
 0x424 | 0x10 | 14:14 | BYP_8B10B | 
@@ -120,8 +122,14 @@ Page | Register | Bits | Feature | Documentation
 0x424 | 0x17 | 08:08 | CFG_MARK_TXSCR_ERR | 
 0x424 | 0x17 | 07:04 | BYP_START | 
 0x424 | 0x17 | 03:00 | BYP_END | 
+**Page** | **Register** | **Bits** | **MAC SerDes 1 - page unknown** | **Absolute 0x2161**
+0x42c | 0x11 | 15:00 | | This is some unknown PLL register - write 0x4000 to diable ring PLL
+**Page** | **Register** | **Bits** | **MAC SerDes 1 - page unknown** | **Absolute 0x2162**
+0x42c | 0x12 | 15:00 | 
 **Page** | **Register** | **Bits** | **MAC SerDes 1 - page unknown** | **Absolute 0x2169**
 0x42d | 0x11 | 00:00 | ANA_RESET
+**Page** | **Register** | **Bits** | **MAC SerDes 1 - page unknown** | **Absolute 0x2171**
+0x42e | 0x11 | 15:00 |
 **Page** | **Register** | **Bits** | **Unknown filter register** | **Absolute 0x2322**
 0x464 | 0x12 | 15:11 | FILTER_0
 0x464 | 0x12 | 10:07 | FORCE