Octagon 5266, Справочное руководство

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Subfunction: 01h
Purpose: To write a single byte to the on–board serial
EEPROM.
Calling registers: AH fch
AL 00h
BX Word address (zero based)
CX Data word to write
DX ffffh (User area relative address)
Return registers: AL Error code
Error code Meaning
ffh Unknown error
01h Function not implemented
02h Defective serial EEPROM
03h Illegal access
Comments: This function writes a word to the user area of
the serial EEPROM.
Programming example:
/* Write 0x1234 to word 3*/
unsigned int seeData = 0x1234;
/* Inline assembly code for Borland C++ 3.1*/
asm {
mov
ax,0fc01h
mov bx,03h /* Write word 3*/
mov cx,seeData/* Get write data from c environment */
mov dx,0ffffh
int 17h
}
Return serial EEPROM size
Function: fch
Subfunction: 04h
Purpose: To obtain the size (bytes) of the on–board serial
EEPROM.
Calling registers: AH fch
AL 04h
DX ffffh
Return registers: BX Size available to user (512 bytes)
AL Error code
Error code Meaning
ffh Unknown error
01h Function not implemented
02h Defective serial EEPROM
03h Illegal access
Comments: This function returns the size (in bytes) of the
serial EEPROM. Since the user cannot access all
of the serial EEPROM, this function determines
how much space is available to the user. This
avoids the user from accessing unavailable
addresses.
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