From: On Behalf Of Joe Barr > I'm forwarding this post by the author of a great little program for > digital amateur radio on Linux, because I'm curious whether or not the > problem he is seeing can be resolved outside the kernel.
From: w1hkj [mailto:[EMAIL PROTECTED] > I am now convinced that the current serial port drivers > available to us > on the Linux platform WILL NOT support CW and/or RTTY that is > software > generated in a satisfactory manner. I don't know what FSK/CW/RTTY/BAUDOT is. > Direct access to the serial port(s) is a kernel perogative in Linux. > Only kernel level drivers are allowed such port access. Not true. > Until such time as new information becomes available I am going to > comment out all references to CW and / or FSK via RTS/DTR. I also > question how useful the FSK on TxD (UART derived) might be to > most users > since the 45.45 baudrate is not available in the serial port driver. > That function will also be commented out. You may be confusing the old-style baud rate lookup table (B9600 et al) with the actual capabilities of the serial port. The lookup table has a limited number of baud rates. You can get more rates than that using a custom divisor. Most motherboard-based serial ports are clocked at 1.8432 Mhz. The UART does 16 samples per bit time, yielding a max baud rate of 115200. 115200 / 25 yields 4608, which is a 1.4% error rate from 4545. This may or may not be acceptable. 115200 / 2535 yields 45.44, which is a 0.01% error rate, which is likely acceptable. > Sorry folks, but we win some and lose some. We make serial port boards with very flexible UARTS. 4545 exactly is achievable. 45.45 too. Linux supported. ..Stu -- We make multiport serial products. http://www.connecttech.com/ (800) 426-8979 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
