Brother HL-Series Technical Reference Manual page 119

Revision C 16/01/96
Free Space Command
ESC*s1M
The amount of memory which is free for use is returned by this command. Two values are returned: the total
amount of free memory and the largest block of free memory.
When you send a value other than 1, an error ( "ERROR = INVALID UNIT" )is returned.
The Free Space command is sent to check the free memory space and you can acknowledge whether the printer
has enough memory for a job or not before you execute your job. Also you can check the amount of memory which
an entity or any other data used.
Free memory space will always be changing during different printing conditions.
*** For example, when the printer receives print data, it is stored in the printer memory. So, the free
space in the printer memory becomes smaller. After the data is printed, the printer memory becomes
empty, so the free space becomes larger again.
Certain action is needed when you decide there is not enough memory to hold the data to be downloaded.
Font Cache
In order to print characters from a scalable font, the printer changes the scalable character outlines into sized
bitmaps. These bitmapped characters are produced on a character-by-character basis and produced bitmapped
characters are stored in memory. As it prints more pages using more fonts, more memory is consumed by the
bitmaps. The bitmap characters used on the first page of a job can stay in memory till the end of a job. These
stored bitmap characters are known as the font cache.
If a Brother HL-10h printer encounters a memory low condition, all of the font cache is automatically deleted.
Also, font cache and temporary entities can be cleared by a Printer Reset command.
Memory Status Response
The total available memory is specified by "TOTAL=" and the largest continuous block size of available memory
is specified by "LARGEST=".
PCL
INFO MEMORY
TOTAL = 10000
LARGEST = 3500
Memory Error Response
When the value field of the free memory command is out of range, the response for this command would be as
follows;
PCL
INFO MEMORY
ERROR = INVALID UNIT
(27)(42)(115)(48)(77)
Chapter 2 "PCL" - 104
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