Documentation++

2 files changed, 27 insertions, 3 deletions

diff --git a/README.md b/README.md
index fdb54e4..d655042 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,29 @@
 # kaxxxxp-viewer - Data Logger and Viewer for KAxxxxP power supplies
 
 **kaxxxxp-viewer** acquires and visualizes voltage and current data from
-KAxxxxP power supplies. These PSUs are equipped with a USB port, which can
-be used both for remote control and data acquisition using a serial protocol.
+KAxxxxP power supplies. These are sold under brand names such as Korad or RND
+Lab and equipped with a USB serial port, allowing them to be used as simple,
+low-resolution measurement devices. See the [sigrok
+wiki](https://sigrok.org/wiki/Korad_KAxxxxP_series) for details.
+
+It has been successfully used with "RND 320-KA3005P" (single-channel) and "RND
+320-KA3305P" (dual-channel) supplies. Observed attributes:
+
+* Time resolution: **a few Hz**
+* Voltage range: 0 .. 30 V
+* Voltage resolution: 10 mV
+* Current range: 0 .. 5 A
+* Current resolution: 1 mA
+
+Voltage and current range depend on the device, the resolutions are probably
+identical.
+
+**Warning:** In addition to reading voltage and current values, the serial
+interface also supports *setting* them. This is not supported by
+kaxxxxp-viewer. However, be warned that communication errors or bugs may cause
+the power supply to receive a write command with an arbitrary voltage or
+current value, which may result in damaged equipment, fire, or other harm. By
+using this software, you acknowledge that you are aware of these risks.
 
 See `bin/kaxxxxp-viewer --help` for usage details.
 
diff --git a/bin/kaxxxxp-viewer b/bin/kaxxxxp-viewer
index 6b7f51f..073b9f5 100755
--- a/bin/kaxxxxp-viewer
+++ b/bin/kaxxxxp-viewer
@@ -9,7 +9,8 @@
 
 DESCRIPTION
 
-kaxxxxp-viewer logs voltage and current readings provided by a KAxxxxP power supply.
+kaxxxxp-viewer logs voltage and current readings provided by a KAxxxxP power supply
+with serial/USB interface, sold under brands such as Korad or RND Lab.
 Measurements can be taken directly (by specifying <measurement duration> in seconds)
 or loaded from a logfile using --load <file>. Data can be plotted or aggregated on stdout.
 
@@ -131,6 +132,8 @@ class KA320:
             return self.reader.get_expected_line()
         return self.reader.get_line()
 
+    # See <https://sigrok.org/wiki/Korad_KAxxxxP_series> for supported commands
+
     def connect(self):
         return self.rw(b"*IDN?", 16)