Pt100 Readme: how to flash the board

diff --git a/pt100/README b/pt100/README
index 74d70c6b0e7147702574f46f20587e0d92a21bf5..4121412eaee5638f8572985be952fa944ad389d2 100644 (file)
--- a/pt100/README
+++ b/pt100/README
@@ -10,7 +10,6 @@
 * The offset of each channel and the global gain can be calibrated manually and corresponding values are stored in the uC memory.
 
 
-
 Serial Data
 -----------
 All measured data is output on a serial interface, running at 38400 8N1. The FT232 adapter board can be used to connect to a USB on any PC. The data format is as follows:
@@ -37,5 +36,11 @@ Display
 -------
 The display shows temperatures of even channels in the left column, odd channels in the right. Negative values are displayed in red. Using the display slightly reduces the sample rate due to the time needed to update the readings. The display is only updated after enough samples are taken to provide the required amount of averaging.
 
+
+Programming
+-----------
+Programming the ATmega 324PA on the board is done using `make program`. It uses the dragon_jtag programmer option of avrdude. The programmer has to be connected to pinheader P1.
+The VTG pin on the dragon is an input (target voltage) and it provides power to the dragon's level shifters. So power the Pt100 board from en external 3.3V supply on the header P2. You may generate the 3.3V from the the additional VCC/GND on the dragon with an LDO.
+
 -- 
 Jan Michel