Machine Characteristics - BIOS Interrupt 0x15-E820
This is one of a number of machine-characteristics.
E820 Report
The 'E820' BIOS call gives a booting real-mode program information about memory ranges in the machine as the BIOS has configured them. How do different machines report the information? The table below shows some examples.
| Machine | First Returned EBX Continuation Value | Continuation Value Increase | Final Continuation Value in EBX | Final Carry Flag | Row Size | Number of Rows* | Range of types |
|---|---|---|---|---|---|---|---|
| Dell Latitude XP 475D laptop. 80486 | 1 | 1 | 0 | 0 | 20 | 2 | 1 only |
| AOpen motherboard. Pentium 3 600MHz. Award BIOS 3.60 | 1 | 1 | 0 | 0 | 20 | 9 | 1 to 4 |
| Acer Travelmate 525TE | 1 | 1 | 0 | 0 | 20 | 7 | 1 to 4 |
| Asus EEE 4G netbook. Celeron M ULV 630MHz. AMI ASUS 701 BIOS | 1 | 1 | 0 | 0 | 20 | 10 | 1 to 4 |
| Award Modular BIOS v4.51pg (1984-1999) | 1 | 1 | 0 | 0 | 20 | 7 | 1 to 4 |
| Viglen MPC-L. Geode 399MHz. ION A503 BIOS | 0x3cd4 | 20 | 0 | 0 | 20 | 8 | 1 to 4 |
| Jetway NC91. Dual-core Atom 1.6GHz. Phoenix-AwardBIOS | 1 | 1 | 0 | 0 | 20 | 10 | 1 to 4 |
| Dell Latitude C600 Phoenix BIOS | 1 | 1 | 0 | 0 | 20 | 5 | 1 to 2 |
| Thin client | 1 | 1 | 0 | 0 | 20 | 7 | 1 to 4 |
| Toshiba Tecra 710CDT | 0x89d8 | 20 | 0 | 0 | 20 | 7 | 1 to 2 |
| Touch screen PC | 1 | 1 | 0 | 0 | 20 | 5 | 1 to 2 |
| 233Mhz Pentium | 1 | 1 | 0 | 0 | 20 | 7 | 1 to 2 |
| 3.2Ghz AMD Phenom II X2 555 (dual core) | 1 | 1 | 0 | 0 | 20 | 10 | 1 to 4 |
| Dell Dimension 8110 (Celeron) | 1 | 1 | 0 | 0 | 20 | 11 | 1 to 4 |
| Toshiba Satellite M65 | 1 | 1 | 0 | 0 | 20 | 15 | 1 to 4 |
| (To be determined) | 1 | 1 | 0 | 0 | 20 | 7 | 1 to 4 |
Notes
- All machines tested supported the e820 call
- Number of Rows may vary due to memory installed
page revision: 4, last edited: 01 Jan 2015 00:18
