Kontron ETXexpress-AI - Manual (Page 124)

Kontron ETXexpress-AI User’s Guide
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9 Appendix A: JIDA Standard
Every board with an on-board BIOS extension supports the following function
calls, which supply information about the board. Jumptec Intelligent Device
Architecture (JIDA) functions are called via Interrupt 15h. Functions
include:
» AH=Eah
» AL=function number
» DX=4648h (security word)
» CL=board number (starting with 1)
The interrupt returns a CL 0 if a board with the number specified in CL does
not exist. CL will equal 0 if the board number exists. In this case, the
content of DX determines if the operation was successful. DX=6B6Fh indicates
success; other values indicate an error.
9.1 JIDA Information
To obtain information about boards that follow the JIDA standard, use the
following procedure.
» Call Get BIOS ID with CL=1. The name of the first device installed will be
returned. If you see the result Board exists (CL=0), increment CL, and call
Get BIOS ID again.
» Repeat until you see Board not present (CL 0). You now know the names of
all boards within your system that follow the JIDA standard.
» You can find out more information about a specific board by calling the
appropriate inquiry function with the board’s number in CL.
NOTE: Association between board and board number may change because of
configuration changes. Do not rely on any association between board and
board number. Always use the procedure described above to determine the
association between board and board number.
Refer to the JIDA manual in the jidai1xx.zip folder, which is available from
the Kontron Web site, for further information on implementing and using JIDA
calls with C sample code.