From b21a13fe3326e5cef1ba565e77b70790ca90998e Mon Sep 17 00:00:00 2001 From: Christian Pointner Date: Tue, 27 Sep 2011 20:25:02 +0000 Subject: added dtmf-bin translation table ihu-mpu communicaton over rs232 not spi git-svn-id: https://svn.spreadspace.org/mur.sat@173 7de4ea59-55d0-425e-a1af-a3118ea81d4c --- doc/protocols/ground-crx.txt | 22 +++++++++++++++++++++- doc/protocols/ihu-mpu.txt | 9 +++------ 2 files changed, 24 insertions(+), 7 deletions(-) diff --git a/doc/protocols/ground-crx.txt b/doc/protocols/ground-crx.txt index 504d914..1a92ab0 100644 --- a/doc/protocols/ground-crx.txt +++ b/doc/protocols/ground-crx.txt @@ -18,7 +18,27 @@ Frame Checksum: --------- -XOR over Signs intrepreted as HEX (0-9A-D#*) -> (0-9A-F) +XOR over Signs intrepreted as 4-bit numbers (see translation table below) + + DTMF-Sign | Number + ------------+---------- + D | 0 + 1 | 1 + 2 | 2 + 3 | 3 + 4 | 4 + 5 | 5 + 6 | 6 + 7 | 7 + 8 | 8 + 9 | 9 + 0 | 10 + * | 11 + # | 12 + A | 13 + B | 14 + C | 15 + Codes: ------ diff --git a/doc/protocols/ihu-mpu.txt b/doc/protocols/ihu-mpu.txt index 9a25432..aa3c5f8 100644 --- a/doc/protocols/ihu-mpu.txt +++ b/doc/protocols/ihu-mpu.txt @@ -5,17 +5,14 @@ Protocol Definition between IHU and MPU Introduction ------------ -The two controllers use SPI to communicate with each other. In -addition to the 4 Lines needed for SPI there are 3 extra connections +The two controllers use RS-232 with TTL-Levels to communicate with each other. +In addition to the 2 Lines needed for RS-232 there are 2 extra connections between IHU and MPU. One is for the IHU to control the power of the MPU. Holding this pin low prevents the MPU from running and therefore keeps power consumption at a minimum also the whole payload electronic connected to the MPU has to be in powerdown when this PIN goes low. The second line is for reset. After a high to low transition the MPU has to perform a hardware reset. This also resets any payload hardware. -The third line is used by the MPU to inform the IHU that it wishes -to communicate. After this line goes high the IHU has to start the -communication by starting the SPI clock. Frames @@ -36,7 +33,7 @@ of the message. In a message N bytes long, where Byte 1 is the first and Byte N the last Byte, CS is calculated starting with Byte 1 (0xAA) and ending with Byte N-1 (last DATA Byte) The minimum frame length is 4 Bytes and the maximum is 260 Bytes. -The bytes have to be sent LSB first. Multi byte fields have to be sent +The bytes have to be sent LSB first. Multi-byte fields have to be sent in Little-Endian format. -- cgit v1.2.3