CognitiveTPG A776 ColorPOS, Руководство по программированию

Страница: 176 / 180

Appendix C: Electronic Journal 164
A776 (B780) Programming Guide A776-PG00001 D 07/13
Journal RAM buffer
Journal data is temporarily buffered in RAM until the printer is triggered to write it to flash. At power up 4K bytes
of RAM will be dynamically allocated. In the unlikely event that 4K bytes are not available, 2K will be allocated. If
for some reason 2K bytes are not available, the electronic journal feature cannot be used. Allocation success or
failure information is available to the interface via commands described below.
Loss of power results in loss of any data currently in the journal RAM buffer.
Triggers that cause the journal data in RAM to be written to flash are:
Knife Cut • command
Write Journal RAM Data to Flash • command (described below)
Printer is idle for 10 seconds •
Reset Printer • command (0x1D 0xFF)
Print To Journal • command (described below)
RAM becomes filled before one of these other triggers occurs. •
The printer goes busy at the communication interface while writing to the journal flash buffer.
Journal Flash buffer
A portion of flash memory is available for the journal flash buffer. By using the Flash Memory User Sectors Allocation
command (0x1D 0x22 0x 55
n1 n2
), the user can allocate the number of 64Kbyte sectors used for logos, user storage,
and journal flash buffer.
If there are X sectors available, the Flash Memory User Sectors Allocation command will allocate n1 sectors to logos,
n2 sectors to user storage, and (X – n1 – n2) sectors for the journal flash buffer. If all available sectors are allocated for
logos and user storage, there is no flash available for the journal.
The firmware default allocation is 1 sector for logos, 1 sector for user storage, and the rest for journal, but this may
be changed at printer build time. Journal flash allocation and flash usage information is available via commands
described below, and is printed on the diagnostics form.
Before erasing flash, check to see if there is journal data stored, and print it out if necessary.
Triggers that cause the journal flash buffer to be cleared are:
Clear Journal command (described below) •
Flash Memory User Sectors Allocation • command (0x1D 0x22 0x 55 n1 n2 ) reallocates flash
memory.
New Flash firmware is downloaded to the printer •
•
Exception Conditions in Auto Journal Mode
When there isn’t enough memory available in the journal flash buffer, the printer beeps at each receipt to signal the
flash full condition. The printer will print a duplicate receipt and cut after it, instead of writing it to flash, and clear
out the RAM buffer. When the trigger for writing to flash is a knife cut (which would be the usual case in Auto Journal
Mode) the customer receipt is easily detached from the duplicate receipt by the operator.
If a receipt is over 4Kbytes in size, and there are less than 4Kbytes available in the journal flash buffer, the printer will
not print a portion of the duplicate receipt in the middle of the original receipt. This portion of the duplicate receipt is
lost.