Reference Manual

PMAC 2 Software Reference
256 PMAC On-Line Command Specification
• the optional second{constant} must be at least as great as the first {constant} – it
represents the number of the end of the range;
• {address} is an integer constant from 0 to 65,535 ($0 to $FFFF if specified in hex).
Note:
No spaces are permitted between the M-variable name and the arrow
double character in this command.
Remarks
This command causes PMAC to define the specified M-variable or range of M-variables to
point to 32 bits of data in the low 16 bits of both X and Y memory at the specified location in
PMAC’s address space. The data is interpreted as a floating-point value with the IEEE
single-precision (32-bit) format.
The definition consists of the letter F, an optional colon (:), and the word address.
This format is only useful for dual-ported RAM locations $D000 to $DFFF (Option 2
required). With this format, the host can read or write to the corresponding location with the
standard IEEE 32-bit floating-point data format.
The IEEE 32-bit floating point format has the sign bit in bit 31 (MSB); the biased exponent
in bits 30 to 23 (the exponent is this value minus 127), and the fraction in bits 22 to 0 (there is
an implied 1 added to the fraction in the mantissa). The words are arranged in the standard
Intel format.
Example
M155->F:$D401
M255->F$D402
See Also
M-Variables (Computational Features)
Dual-Ported RAM (Writing a Host Communications Program)
On-line commands M{constant}, M{constant}->,
..........M{constant}->DP:{address}, M{constant}={expression}
Program command M{constant}={expression}
M{constant}->L:{address}
Function
Long Word Floating-Point M-Variable Definition
Scope
Scope
Syntax
M{constant}[..{constant}]->L[:]{address}
where:
• {constant} is an integer from 0 to 1023 representing the number of the M-variable;
• the optional second{constant} must be at least as great as the first {constant} – it
represents the number of the end of the range;
• {address} is an integer constant from 0 to 65,535 ($0 to $FFFF if specified in hex).
Note:
No spaces are permitted between the M-variable name and the arrow
double character in this command.
Remarks
This command causes PMAC to define the specified M-variable or range of M-variables to
point to a long word (48 bits) of data – both X and Y memory – at the specified location in
PMAC’s address space. The data is interpreted as a floating-point value with PMAC’s own
48-bit floating-point format.
The definition consists of the letter L, an optional colon (:), and the word address.
Memory locations for which this format is useful are labeled with ‘L:’ in the memory map.