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-rw-r--r--doc/protocols/ihu-ttx.txt22
1 files changed, 11 insertions, 11 deletions
diff --git a/doc/protocols/ihu-ttx.txt b/doc/protocols/ihu-ttx.txt
index 2fc518c..2260968 100644
--- a/doc/protocols/ihu-ttx.txt
+++ b/doc/protocols/ihu-ttx.txt
@@ -6,13 +6,13 @@ Bitstream
---------
IHU and TTX communicate using a simple serial synchronous bus (SDA,SCL).
-The IHU is the master and drives the clock. On Idle the SCL and SDA are both
-at logic 0. When the IHU want's to communicate it has to generate wakeup pulse
+The IHU is the master and drives the clock. On idle the SCL and SDA are both
+at logic 0. When the IHU want's to communicate it has to generate a wakeup pulse
with a minimun length of 1µs. After this it has to wait at least 3ms for the TTX
-wake up and switch to a higher oscillator frequency. The data is transferred in
-octets MSB first. SDA must be stable before the clock goes high. A Clock pulse
-must be at least 4µs long and the data has to stay valid for at least 17µs. After
-each octet there must be a break of 50µs.
+to wake up and switch to a higher oscillator frequency. The data is transferred
+MSB first in groups of 8bits (1 Octet). SDA must be stable before the clock goes
+high. A Clock pulse must be at least 4µs long and the data has to stay valid for
+at least 17µs. After each octet there must be a break of 50µs.
| wake up | 1st octet | break | 2nd octet
_________________ _________________
@@ -29,11 +29,11 @@ Frames
------
Every frame starts with 4 bit command code and a 4 bit length field. After this follow
-len octets of data. When all the data has been transferred the Master (IHU) switches
-SDA as input and clocks in on byte as acknowledge. The aknowledge is a one byte XOR
+len octets of data. When all the data has been transferred the master (IHU) switches
+SDA to input and clocks in on byte as acknowledge. The aknowledge is a one byte XOR
checksum over all octets (including the command/len octet).
-Field-length: 1 LEN 1
+Field-length: 1 LEN 1
+---------+----------------+--------+
Name | CMD/LEN | DATA | CS |
+---------+----------------+--------+
@@ -68,7 +68,7 @@ Commands
Hex 'A'
~~~~~~~
- This instructs the TTX to send out a aknowledge frame over cw. The command
+ This instructs the TTX to send out an aknowledge frame over cw. The command
has 1 octet of data containing the ASCII Code of the aknowledge to send out.
Hex 'B'
@@ -76,7 +76,7 @@ Commands
This inscructs the TTX to send out a beacon immediately. It also resets the timer
so that the next beacon will follow after the normal beacon period. This command has
- no data
+ no data.
Hex 'F'
~~~~~~~