diff --git a/README.md b/README.md
index 6e63587..86bea7a 100644
--- a/README.md
+++ b/README.md
@@ -4,9 +4,18 @@
 
 |Timer|  Type  | Usage                         | Mode                   | used ISRs      | Output connected
 |-----|--------|-------------------------------|------------------------|----------------|------------------
-|  0  |  8 bit | Millis Tick Timer             | 2 (CTC)                | COMPA          | -
+|  0  |  8 bit | Millis Tick Timer (1kHz)      | 2 (CTC)                | COMPA          | -
 |  1  | 16 bit |                               |                        |                |
-|  2  |  8 bit | Modbus Tick Timer             | 2 (CTC)                | COMPA          | -
+|  2  |  8 bit | Modbus Tick Timer (10kHz)     | 2 (CTC)                | COMPA          | -
 |  3  | 16 bit | Step Signal Abzugsrolle       | 8 (PWM, Phase & Freq.) | -              | OC3B / PE4
 |  4  | 16 bit | Step Signal Taenzer           | 8 (PWM, Phase & Freq.) | OVF, ~~COMPA~~ | OC4A / PH3
 |  5  | 16 bit | Step Signal Rotation Spule    | 8 (PWM, Phase & Freq.) | -              | OC5C / PL5
+
+### UART
+
+|UART| Usage
+|----|----------------------------------
+|  0 | Debug Prints (connected to USB)
+|  1 |
+|  2 |
+|  3 | Modbus (connected to MAX485)