LMS-6 Radiosonde/APRS Firmware Mod

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Introduction

This page is a list of tasks and firmware modules that will be required to convert LMS-6 radiosondes into APRS 9600 baud 70-centimeter amateur radio trackers. See the parent page for reverse engineering information for the LMS-6 as-is.

Modules

Owner Module Status Notes
N0RC Programmer(ICC) in-progress Haven't connected over ICC yet, but do have XP VM running programming software.

Communications were established with the programming tool. Suspect wiring issue.

N0RC Backup firmware waiting on programmer Once ICC is up, try to read the existing firmware to save a copy. May also analyze as a tool to figure out which pins do what, and how conversion functions are implemented.
N0RC Programming Adapter requirements gathering Figure out which pins from the edge-connector to bring out to debug connectors. We'd like to be able to plug in a standard ST7 programmer to the adapter for easy reprogramming.
KD0LIX Debug UART in-progress We can turn an unused GPIO into a software UART by bit-banging. Since we have to disable interrupts to keep the timing correct, a fast baud-rate is best, like 16MHz Fcpu -> 1mbps UART baud rate
GPS Driver research The GPS is attached to the UART port at 38400 baud. Need to figure out which of several supported protocols are in use and write or source a parser. Be aware that we will likely drop UART data while transmitting with the CC1050 radio.
APRS Packetizer research Need to create APRS frames
CC1050 Controller research Module to configure the CC1050 into an appropriate TX mode, startup, lock PLL and so forth
CC1050 Bitstream research Module to stream out APRS packet one bit at a time as the CC1050 requests them. Will likely need to disable interrupts for a significant amount of time to prevent bit-jitter
Temperature Sensor research We don't currently know how this temperature sensor works.
Humidity Sensor research Appears to be some sort of capacitance to frequency converter, need a module to measure frequency and convert to humidity. May also need to account for temperature as there appears to be a temperature probe cosited with the hygro.