CognitiveTPG A799 - Manual (Page 115)

Chapter 4: Programming Commands 115 Revision D 12/09
A799-PG00001D
User storage status (ColorPOS ® )
ASCII GS 0x97 m n
Hexadecimal 1D 97 m n
Decimal 29 151 m n
Value of m: m specifies the type of stored object to be reported:
m = 0 return the kilobytes (1024) of free user RAM,
n = 0 gets largest free block size
n = 1 gets the total size free
m = 1 return the kilobytes of free character & logo flash memory, n = 0
m = 3 return the CRC of a logo indexed by n
m = 5 return the CRC of a macro that has been stored, n = 0
For m = 0 the value of n selects a return of either the largest free block or total free size, since contiguous allocation cannot
be assumed as this area is completely under user control through address parameters.
n = 0 if only one instance of an object type is allowed (macro, user data, user defined characters).
n is the item index when more than one object of type m is possible
n <= FE, see the comments about logo and character set indexes
n = FF : return a list describing all the existing items of type m
Note: When a specific item request is made, a returned CRC value of 0 0 indicates that no item is stored at that index.
There is a practically negligible possibility that a valid object will have a 0 0 CRC; if this is of concern, applications
should check the object downloaded byte sequence to verify that this is not the case (as well as store the CRC as an “ID”
for the object if needed later for return value comparisons).
Downloaded character sets are identified by integer extending the existing code page selection as enumerated in the select
international character set (= select character code table) command. The firmware standard list is incrementally extended
each time a new single or double byte set is downloaded.
Single byte downloaded fonts are selected by m = 3 and 0x40 <= n < 0x80.
Since there are only three double-byte character sets supported, the value 0x80 / 0xA0 / 0xC0 selects the first, second, third
downloaded double byte font respectively. In return, each downloaded double byte character band is reported individually
as 0xC0, 0xC1, 0xC2 … for as many bands as have been defined.
This command returns the state of occupancy of available flash storage and user RAM. The printer response for each item
is a 4 byte header, 0x1D 0x97 nL nH (number of bytes that follow in the response) and for each item a 4 byte structure: 1
st
m (type) byte, 2 nd n index byte followed by a 2 byte CRC in Lo Hi order of the data string in that storage space.
The return for m = 0–2 is the header and one 4-byte item giving remaining storage space in the CRC position in
Lo Hi order: 1D 97 4 0 m 0 fL fH, where f is the kBytes of storage remaining. Note that RAM storage space is not content
typed, while available flash is statically divided into logo, character set, and user data types. Change of the divisions is
possible via flash erasure and flash allocation commands.
If the communication protocol is RS-232C – Xon/Xoff, then “X symbol substitution response” should be configured with
the setting communications parameters command (US STX , 1F 02).