src/tcl/target/readme.txt

   1 Prerequisites:
   2 The users of OpenOCD as well as computer programs interacting with OpenOCD are expecting that certain commands
   3 do the same thing across all the targets.
   4
   5 Rules to follow when writing scripts:
   6
   7 1. The configuration script should be defined such as , for example, the following sequences are working:
   8         reset
   9         flash info <bank>
  10 and
  11         reset
  12         flash erase_address <start> <len>
  13 and
  14         reset init
  15         load
  16
  17 In most cases this can be accomplished by specifying the default startup mode as reset_init (target command
  18 in the configuration file).
  19
  20 2. If the target is correctly configured, flash must be writable without any other helper commands. It is
  21 assumed that all write-protect mechanisms should be disabled.
  22
  23 3. The configuration scripts should be defined such as the binary that was written to flash verifies
  24 (turn off remapping, checksums, etc...)
  25
  26 flash write_image [file] <parameters>
  27 verify_image [file] <parameters>
  28
  29 4. jtag_khz sets the maximum speed (or alternatively RCLK). If invoked
  30 multiple times only the last setting is used.
  31
  32 interface/xxx.cfg files are always executed *before* target/xxx.cfg
  33 files, so any jtag_khz in interface/xxx.cfg will be overridden by
  34 target/xxx.cfg. jtag_khz in interface/xxx.cfg would then, effectively,
  35 set the default JTAG speed.
  36
  37 Note that a target/xxx.cfg file can invoke another target/yyy.cfg file,
  38 so one can create target subtype configurations where e.g. only
  39 amount of DRAM, oscillator speeds differ and having a single
  40 config file for the default/common settings.
  41