Opcode PatchTalk User Guide - House of Synth

It is defined as a Pascal procedure to allow Pascal programmers towrite PCmds. The handle dataHandle consists of the data specified byListOfValues. It is modified directly by the procedure to return theresult. When it returns, the data in the handle is placed in the variablespecified by Destination. Note that dataHandle is not locked.The C code for Checksum and Checksum0 is supplied in the files“Checksum.c” and “Checksum0.c” respectively. Feel free to use thesefunctions as starting points for your own PCmds. If you don't have adevelopment system and you really need a custom function, get afriend to do it for you in exchange for the module you're writing(assuming she owns Galaxy).The code resource must have type ‘PCmd’ and the same name as specifiedby CommandName.General External Commands (*Cmds)When a PCmd is not powerful enough to accomplish the task at hand,consider writing a more general external command, a *Cmd. *Cmdsallow an arbitrary number of numeric and variable parameters to bepassed to them. They perform a task by altering memory, just like aPCmd, but they are more powerful, since they accept more input. Inaddition, they allow a more specific error message to be given in casethey don’t succeed.Their PatchTalk syntax is:CommandName arg1, arg2, arg3, …, argNAs with PCmds, *Cmds are code resources that are called according toPascal calling conventions. They also take a single argument. But thisis where they differ. The argument is a parameter block—a structurecontaining all the parameters. The following is a list of constant valuesfollowed by the basic structure of the parameter block.The args (the arguments) are numeric expressions and string variablesseparated by commas./** Error Types (for resultCode)*/enum { NoError, BadParamCount, NeedMemoryError, GeneralFailure,CustomErrorMsg };/** Parameter Types (for paramType) */enum { NumericType = 1, StringType = 2 };Opcode Publication 1950906 - 35 - PatchTalk Guide