diff --git a/src/platforms/hosted/Readme.md b/src/platforms/hosted/Readme.md index 13324182..a3f31c43 100644 --- a/src/platforms/hosted/Readme.md +++ b/src/platforms/hosted/Readme.md @@ -73,7 +73,7 @@ REMOTE_BMP is a "normal" BMP usb connected ## Device matching As other USB dongles already connected to the host PC may use FTDI chips, -cable descriptions are provided to match with the dongle. +cable descriptions must be provided to match with the dongle. To match the dongle, at least USB VID/PID that must match. If a description is given, the USB device must provide that string. If a serial number string is given on the command line, that number must match @@ -125,6 +125,11 @@ together with the 'r' argument. As the FTDI has more pins, these pins may be used to control enables of buffers and multiplexer selection in many variants. +### FTDI SWD speed +SWD read needs two USB round trip, one for the acknowledge and one +round-trip after the data phase, while JTAG only needs one round-trip. +For that, SWD read speed is about half the JTAG read speed. + ### Reset, Target voltage readback etc The additional pins may also control Reset functionality, provide information if target voltage is applied. etc. @@ -139,11 +144,3 @@ is welcome. ### Discussions on Discord. You can find the Discord link here: https://1bitsquared.com/pages/chat ### Blackmagic mailing list http://sourceforge.net/mail/?group_id=407419 - -## Known deficiencies -### For REMOTE_BMP -#### On windows, the device node must be given on the command line -Finding the device from USB VID/PID/Serial in not yet implemented -### FTDI MPSSE -#### No auto detection -Cable description must be given on the command line