INT 15 - Intel System Management Bus - REQUEST AX = 53B0h BH = 10h BL = protocol (see #00487) CH = device address CL = device command (see #00488) DH = MSB Data or block length (for BlockWrite) DL = LSB Data or first byte of block (for BlockWrite) Return: CF clear if successful AH = 00h or 80h (SMBus(System Management Bus) A derivative of the I2C bus used for communication between various components of a computer, such as smart batteries and their chargers. In contrast to I2C, SMBus specifies fixed voltage levels (instead of relative to the power supply voltage) and a 10 KHz minimum clock rate (I2C minimum is 0). SMBus also specifies several timings which are not required by I2C. See also I2C, ACCESS.bus. OK) (80h indicates a previously unreported SMI took place) CF set if error AH = error code (05h,10h,11h,12h,13h,14h,17h,19h,1Ah,86h) (see #00484) Desc: request access to a device on the SMBus(System Management Bus) A derivative of the I2C bus used for communication between various components of a computer, such as smart batteries and their chargers. In contrast to I2C, SMBus specifies fixed voltage levels (instead of relative to the power supply voltage) and a 10 KHz minimum clock rate (I2C minimum is 0). SMBus also specifies several timings which are not required by I2C. See also I2C, ACCESS.bus. SeeAlso: AX=53B0h/BH=11h, AX=53B0h/BH=13h (Table 00487) Values for Intel System Management Bus protocol codes: 00h Quick Command 01h Send Byte 02h Receive Byte 03h Write Byte 04h Read Byte 05h Write Word 06h Read Word 07h Block Write 08h Block Read 09h Process Call 0Ah-FFh reserved SeeAlso: #00488 (Table 00488) Values for Intel System Management Bus Smart Battery command codes: Cmd Protocol(s) Description 00h Rd/Wr Word "ManufacturerAccess" implementation-specific 01h Rd/Wr Word get/set Low Capacity Alarm threshold 02h Rd/Wr Word get/set Remaining Time Alarm value (in minutes) 03h Rd/Wr Word get/set battery characteristics (see #00489) 04h Rd/Wr Word "AtRate" indicate charge/discharge rate 05h Read Word "AtRateTimeToFull" time to completely charge (in min.) 06h Read Word "AtRateTimeToEmpty" time to entirely discharge (min.) 07h Read Word "AtRateOK" boolean: can battery supply another 10sec? 08h Read Word internal battery temperature (in 0.1 Kelvins) 09h Read Word current battery voltage in millivolts 0Ah Read Word current flowing through battery in milliamperes (positive if charging, negative if discharging) 0Bh Read Word average current over the past minute 0Ch Read Word expected error margin in capacity computations in % 0Dh Read Word predicted remaining charge as % of full charge 0Eh Read Word predicted remaining charge as % of design capacity 0Fh Read Word predicted remaining charge in mAh or 10mWh 10h Read Word predicted full charge capacity in mAh or 10mWh 11h Read Word predicted remaining battery life in minutes FFFFh = not discharging 12h Read Word rolling average of predicted life over past minute 13h Read Word rolling average of predicted charge time over past min. FFFFh = not charging 14h Read Word get battery's desired charging current in mA 14h Write Word set charging current in mA 15h Read Word get battery's desired charging current in mV 15h Write Word set desired charging voltage in mV 16h Read Word get current battery status (see #00490) 17h Read Word get number of charge/discharge cycles for battery 18h Read Word get design capacity in mAh or 10mWh 19h Read Word get design voltage 1Ah Read Word get specification information (see #00491) 1Bh Read Word get manufacture date (see #01665 at INT 21/AX=5700h) 1Ch Read Word get serial number 1Dh-1Fh reserved 20h Read Block get manufacturer's name 21h Read Block get device name 22h Read Block get device chemistry (see #00492) 23h Read Block get manufacturer data 24h-2Eh reserved 2Fh manufacturer-specific 30h-3Bh reserved 3Ch-3Fh manufacturer-specific Note: bits 7-6 are reserved for addressing multiple batteries in a future version of the specification SeeAlso: #00487 Bitfields for Smart Battery battery characteristics: Bit(s) Description (Table 00489) 0 battery has internal charge controller (read-only) 1 primary/secondary battery support (read-only) 6-2 reserved 7 conditioning cycle requested 8 internal charge controller enabled 9 battery operating in primary mode 13-10 reserved 14 disable broadcast to charger 15 report capacity in units of 10mW / 10mWh instead of mA / mAh SeeAlso: #00488,#00490 Bitfields for Smart Battery battery status: Bit(s) Description (Table 00490) 15 overcharged 14 terminate-charge alarm 13 reserved 12 over-temperature alarm 11 terminate-discharge alarm 10 reserved 9 remaining-capacity alarm 8 remaining-time alarm 7 initialized 6 charging 5 fully charged 4 fully discharged 3-0 error codes 0000 OK 0001 busy 0010 reserved command 0011 unsupported command 0100 access denied (tried to write to read-only value) 0101 overflow/underflow 0110 bad size 0111 unknown error SeeAlso: #00488,#00489,#00491 Bitfields for Smart Battery specification information: Bit(s) Description (Table 00491) 3-0 SmartBattery specification minor revision number 7-4 SmartBattery specification version number 11-8 voltage scaling (0-3, multiply voltages by 10^scale) 15-12 current scaling (0-3, multiply currents by 10^scale) SeeAlso: #00488,#00490 (Table 00492) Values for Smart Battery device chemistry (not case-sensitive): "LION" Lithium ion "NiMH" Nickel metal hydride "PbAc" lead-acid "NiCd" Nickel Cadmium "NiZn" Nickel Zinc "RAM(Random Access Memory) See also DRAM, SRAM." rechargeable Alkaline Manganese "ZnAr" Zinc-Air SeeAlso: #00488