The EtherSmart Wildcard Glossary

C Type Abbreviations Used in Function Declarations

Standard C type specifiers such as char, int, and long are used in the glossary declarations. In addition, we use four convenient typedefs that are defined in the TYPES.h header file:

typedef unsigned char	uchar;
typedef unsigned int	uint;
typedef unsigned long	ulong;
typedef unsigned long	xaddr;

The meanings of the first three typedefs are obvious; they are abbreviations for unsigned types. The “xaddr” typedef means “extended address”, and is used when a 32-bit address parameter is passed. The least significant 16-bits of the xaddress specify the standard 16-bit machine address, and the most significant 16-bits specify the page.

Any other required C typedefs are described in the text of the relevant glossary entry.

Forth Stack Symbols

The following table describes the standard symbols used to represent items placed on the Forth data stack.

Stack Symbol	Size on Stack	Size in Memory	Valid Data Size	Meaning
addr	1 cell	2 bytes	2 bytes	16-bit address. Range: 0 to 65,535 (0-0xFFFF).
page	1 cell	2 bytes	1 byte	Page. Range: 0 to 0x3F on PDQ platforms, 0 to 0xFF on earlier platforms.
xaddr	2 cells	4 bytes	3 bytes	32-bit extended address comprising an address and page: addr\page.
xmailbox	2 cells	4 bytes	3 bytes	Extended address of a mailbox variable.
xcfa	2 cells	4 bytes	3 bytes	Code field xaddr (execution address, corresponding to a 32-bit function pointer in C)
flag	1 cell	2 bytes	2 bytes	Boolean flag, 0 indicates false. Non-zero indicates true.
true	1 cell	2 bytes	2 bytes	Boolean flag, = -1 = 0xFFFF.
false	1 cell	2 bytes	2 bytes	Boolean flag, = 0
char	1 cell	1 byte	1 byte	ASCII character.
count	1 cell	2 bytes	2 bytes	A string count. While standard Forth strings are restricted to 1-byte counts, this library employs “long strings” and “long buffers” with 2-byte counts, supporting up to 65,533 bytes in the string.
cnt	1 cell	2 bytes	2 bytes	Synonym for count
bufsize	1 cell	2 bytes	2 bytes	A buffer size that constrains the maximum number of characters that can be stored in the buffer. 0- 65,535.
xstring	2 cells	4 bytes	3 bytes	Extended address of the first data-containing byte of a string.
xbuffer	2 cells	4 bytes	3 bytes	Extended address of a buffer.
xbuffer	2 cells	4 bytes	3 bytes	Extended address of a buffer.
xlbuffer	2 cells	4 bytes	3 bytes	Extended address of a “long buffer” comprising a 2-byte count followed by the buffer data.
n	1 cell	2 bytes	2 bytes	Signed 16-bit (single) integer. Range: -32,768 to 32,767.
u	1 cell	2 bytes	2 bytes	Unsigned 16-bit (single) integer range: 0 to 65,535.
d	2 cells	4 bytes	4 bytes	32-bit integer. Used to represent encryption keys.
task_base	1 cell	2 bytes	2 bytes	16-bit address. Range: 0 to 65,535 (0-0xFFFF), the base address in common RAM of a task area (typically 1 Kbyte long).
timeout_msec	1 cell	2 bytes	2 bytes	Unsigned 16-bit (single) integer range: 0 to 65,535, representing the number of milliseconds before a timeout for the operation.
modulenum	1 cell	2 bytes	1 byte	Integer that specifies the module number (hardware address) of a Wildcard I/O module. Range: 0 to 7. The modulenum must correspond to the 2-bit hardware jumper setting of the target Wildcard combined with its Wildcard bus position (0 or 1) as the top bit of the 3-bit code.

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The EtherSmart Wildcard Glossary

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C Type Abbreviations Used in Function Declarations

Forth Stack Symbols