add TM1637 writing commands

F0-nolib/TM1637/Readme.md

@@ -0,0 +1,26 @@
+4-digit "time" LED indicator based on TM1637
+=============================
+
+FOR STM32F051!!!
+WARNING! Only writing data!!! Can't read keys state.
+
+## GPIO
+- I2C: PB6 (SCL) & PB7 (SDA)
+- USART1: PA9/PA10
+
+## UART 
+115200N1, not more than 100ms between data bytes in command.
+To turn ON human terminal (without timeout) send "####".
+
+## Protocol
+All commands are in brackets: `[ command line ]`.
+
+'[' clears earlier input; '\n', '\r', ' ', '\t' are ignored.
+All messages are asynchronous!
+
+## Commands
+0..9 - send data
+A - display 'ABCD'
+G - get keyboard status (don't work)
+Hhex - display 'hex' as hex number
+Nnum - display 'num' as decimal number