Hi, I've played a bit with osmocom on a C155 here, but there seems to be an issue with the UART/puts/printf code somewhere. I'm using latest git as of today. $ src/host/osmocon > ./osmocon -m c155 -p /dev/ttyUSB0 ../../target/firmware/board/compal_e99/hello_world.bin got 2 bytes from modem, data looks like: 00 00 got 5 bytes from modem, data looks like: 1b f6 02 00 41 got 1 bytes from modem, data looks like: 01 got 1 bytes from modem, data looks like: 40 Received PROMPT1 from phone, responding with CMD read_file(../../target/firmware/board/compal_e99/hello_world.bin): file_size=18560, hdr_len=4, dnload_len=18567 got 1 bytes from modem, data looks like: 1b got 1 bytes from modem, data looks like: f6 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 00 got 1 bytes from modem, data looks like: 41 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 43 Received PROMPT2 from phone, starting download handle_write(): 4096 bytes (4096/18567) handle_write(): 4096 bytes (8192/18567) handle_write(): 4096 bytes (12288/18567) handle_write(): 4096 bytes (16384/18567) handle_write(): 2183 bytes (18567/18567) handle_write(): finished got 1 bytes from modem, data looks like: 1b got 1 bytes from modem, data looks like: f6 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 00 got 1 bytes from modem, data looks like: 41 got 1 bytes from modem, data looks like: 03 got 1 bytes from modem, data looks like: 42 Received DOWNLOAD ACK from phone, your code is running now! Hello World from apps/hello_world/main.c program code At this point there seems to be a hang. However, it looks like the LCD is being partially initialized (?), at least the backlight is enabled and there's a white screen (no "Hello world" on it though). I assume this is because the display driver for C155 is not yet fully merged? Also, the wiki says "The LCD controller inside the display is a Ultrachip UC1682", is this really correct? The code has "ssd1783" as display driver name. Anyway, after removing a newline and some print functions I see some more output (see attached patch for what I changed), which is why I expect a problem in puts/printf, the UART, or the \n handling etc: $ src/host/osmocon > ./osmocon -m c155 -p /dev/ttyUSB0 ../../target/firmware/board/compal_e99/hello_world.bin got 7 bytes from modem, data looks like: 1b f6 02 00 41 01 40 Received PROMPT1 from phone, responding with CMD read_file(../../target/firmware/board/compal_e99/hello_world.bin): file_size=18404, hdr_len=4, dnload_len=18411 got 1 bytes from modem, data looks like: 1b got 1 bytes from modem, data looks like: f6 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 00 got 1 bytes from modem, data looks like: 41 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 43 Received PROMPT2 from phone, starting download handle_write(): 4096 bytes (4096/18411) handle_write(): 4096 bytes (8192/18411) handle_write(): 4096 bytes (12288/18411) handle_write(): 4096 bytes (16384/18411) handle_write(): 2027 bytes (18411/18411) handle_write(): finished got 1 bytes from modem, data looks like: 1b got 1 bytes from modem, data looks like: f6 got 1 bytes from modem, data looks like: 02 got 1 bytes from modem, data looks like: 00 got 1 bytes from modem, data looks like: 41 got 1 bytes from modem, data looks like: 03 got 1 bytes from modem, data looks like: 42 Received DOWNLOAD ACK from phone, your code is running now! Device ID code: 0xb4fbDevice Version code: 0x0000 Here it hangs after the newline in the "Device Version code" line. Any ideas what the problem could be? Thanks, Uwe. -- http://www.hermann-uwe.de | http://www.randomprojects.org http://www.crazy-hacks.org | http://www.unmaintained-free-software.org