820-00850 – Apple A1989
820-00850 is the Apple main board used in the Apple A1989 and Apple MacBook Pro 13. 8 files are indexed for this board: 4 BIOS files, 3 schematics and 1 boardview.
Revisions seen in file names: A. BIOS images are 4 MB. The earliest file dates from August 2019 (Schematics & Boardviews Archive, BIOS Archive and Cyberlan Electronics).
BIOS dumps 4
Schematics 3
Boardviews 1
Board facts
| Board number | 820-00850 |
|---|---|
| Numbering | Apple board number |
| Revisions | A |
| BIOS chip size | 4 MB |
| First seen | 2019-08-01 |
| Source channels | Schematics & Boardviews Archive, BIOS Archive, Cyberlan Electronics |
| About the number | Apple logic boards are numbered 820-xxxx or 820-xxxxx; the trailing letter is the revision. |
Apple models for this logic board
| A-number | Model | Years |
|---|---|---|
| A1989 | MacBook Pro 13-inch, four Thunderbolt 3 ports | 2018–2019 |
A-numbers come from the file names; the model names and years are Apple's published identifiers.
Laptops that use 820-00850
- Apple A1989
- Apple MacBook Pro 13
What these files are for
A BIOS dump is a full image of the board's SPI flash chip. It is written back with an SPI programmer when the original firmware is corrupted, after a chip replacement, or to recover from a failed update. Read and save the original chip first: serial number, DMI data and the Intel ME / AMD PSP state differ between boards.
A schematic is the circuit diagram of the main board: power rails, power-up sequence, component values and net names. It is the reference for measuring voltages and tracing a fault.
A boardview is the component placement map of the PCB: click a part or a net and the viewer highlights where it is and what it connects to. Used together with the schematic to find test points.
Tools to open these files
| Format | What it is | Open with |
|---|---|---|
| .bdv | Honhan .bdv boardview | OpenBoardView, FlexBV or Honhan BoardViewer |
| .bin | raw SPI flash image | a CH341A, XGecu T48 / TL866II Plus or RT809H programmer |
| .brd | .brd boardview (Test_Link format) | OpenBoardView, FlexBV or BoardViewer |
| PDF schematic | any PDF reader; Sumatra PDF and Foxit handle large schematics well | |
| .rar | RAR archive | 7-Zip or WinRAR |
| .rom | raw BIOS ROM image | a CH341A, XGecu or RT809H programmer |
| .zip | ZIP archive | 7-Zip, WinRAR or the built-in Windows extractor |
Questions
Is there a boardview for 820-00850?
Yes, 1 boardview file in .bdv and .brd format.
What BIOS chip size does 820-00850 use?
The BIOS images for 820-00850 are 4 MB.
Which laptops use the 820-00850 board?
Files in the catalog link 820-00850 to the Apple A1989 and Apple MacBook Pro 13.
Where do the download links go?
Each button opens the original public Telegram post the file was shared in. ChambersDesignInc.com only indexes and cross-references those posts.