-Plan for hosted scripting support in OpenOCD\r
-============================================\r
-Jim Tcl support in OpenOCD currently exists as a patch.\r
-\r
-There has been some discussion on the list as to what\r
-purpose scripting support might serve in OpenOCD.\r
-\r
-Also Lua was proposed as a scripting language, but \r
-only Jim Tcl has been forwarded as a patch.\r
-\r
-Tcl is also backwards syntax compatible with OpenOCD \r
-commands.\r
-\r
-Uses of scripting\r
-=================\r
-\r
-Default implementation of procedures in tcl/procedures.tcl.\r
-\r
-- Polymorphic commands for target scripts.\r
- - produce <file> <serialnumber>. Default implementation\r
- is to ignore serial number and write a raw binary file\r
- to beginning of first flash. \r
- - reset handling. Precise control of how srst, trst & \r
- tms is handled and when.\r
-
\ No newline at end of file
+Plan for hosted scripting support in OpenOCD
+============================================
+
+What scripting will not do
+==========================
+It is not the intention that normal OpenOCD users will
+use tcl scripting extensively, write lots of clever scripts,
+or contribute back to OpenOCD.
+
+The scripting support is intended for developers of OpenOCD.
+
+Target scripts can contain new procedures that end users may
+tinker to their needs without really understanding tcl.
+
+Since end users are not expected to mess with the scripting
+language, the choice of language is not terribly important
+to those same end users.
+
+Jim Tcl was chosen as it was easy to integrate, works
+great in an embedded environment and Øyvind Harboe
+had experience with it.
+
+Uses of scripting
+=================
+Default implementation of procedures in tcl/procedures.tcl.
+
+- Polymorphic commands for target scripts.
+ - there will be added some commands in Tcl that the target
+ scripts can replace.
+ - produce <productionfile> <serialnumber>. Default implementation
+ is to ignore serial number and write a raw binary file
+ to beginning of first flash. Target script can dictate
+ file format and structure of serialnumber. Tcl allows
+ an argument to consist of e.g. a list so the structure of
+ the serial number is not limited to a single string.
+ - reset handling. Precise control of how srst, trst &
+ tms is handled.
+- replace some parts of the current command line handler.
+ This is only to simplify the implementation of OpenOCD
+ and will have no externally visible consequences.
+ Tcl has an advantage in that it's syntax is backwards
+ compatible with the current OpenOCD syntax.
+- external scripting. Low level tcl functions will be defined
+ that return machine readable output. These low level tcl
+ functions constitute the tcl api. flash_banks is such
+ a low level tcl proc. "flash banks" is an example of
+ a command that has human readable output. The human
+ readable output is expected to change inbetween versions
+ of OpenOCD. The output from flash_banks may not be
+ in the preferred form for the client. The client then
+ has two choices a) parse the output from flash_banks
+ or b) write a small piece of tcl to output the
+ flash_banks output to a more suitable form. The latter may
+ be simpler.
+
+
+External scripting
+==================
+The embedded Jim Tcl interpreter in OpenOCD is very limited
+compared to any full scale PC hosted scripting language.
+
+The goal is to keep the internal Jim Tcl interpreter as
+small as possible and allow any advanced scripting,
+especially scripting that interacts with the host,
+run on the host and talk to OpenOCD via the TCP/IP
+scripting connection.
+
+Another problem with Jim Tcl is that there is no debugger
+for it.
+
+With a bit of trickery it should be possible to run Jim
+Tcl scripts under a Tcl interpreter on a PC. The advantage
+would be that the Jim Tcl scripts could be debugged using
+a standard PC Tcl debugger.
+
+The rough idea is to write an unknown proc that sends
+unknown commands to OpenOCD.
+
+Basically a PC version of startup.tcl. Patches most
+gratefully accepted! :-)
projects / fw / openocd / blobdiff