DOC: Fix bitstream switch, add more notes about bitstream version

doc/guide/building-examples.md

@@ -43,7 +43,10 @@ currently at the root directory of your local `sonata-system` git repository.
 
 ## Building All Examples
 
->TODO: These environmental variables don't seem to be used by CMAKE but would need to be based.
+> TODO: We should tell them where to get the SW. And especially point out it must match
+> the bitstream version again (all downloaded at one point).
+
+> TODO: These environmental variables don't seem to be used by CMAKE but would need to be based.
 > So these instructions are broken but kept as a starting point.
 
 To build, run the following from the root of the directory which will build the examples:

doc/guide/fpga-update.md

@@ -1,8 +1,12 @@
 # Reloading the FPGA Image
 
 The first thing you should do before building the firmware is to get the latest version of the FPGA image, called the "bitstream". This contains the configuration
-for the microcontroller core & peripherals. The bitstream *must* match the configuration you use to build the software, as if your software expects your
-configuration to have four UART peripherals, but your configuration only has one, you are going to have a bad time!
+for the microcontroller core & peripherals. The "release version" of the bitstream *must* match the
+configuration you use to build the software, as if the bitstream is a different version than what
+the software is expecting, you are not going to have fun!
+
+When you download a release from the Sonata System page, you'll have a matching bitstream and
+software setup.
 
 While you can build your own bitstream as described
 in [FPGA Development](../dev/fpga-development.md), we recommend starting with our prebuilt bitstream first. Building the bitstream requires
@@ -29,7 +33,7 @@ to overwrite any of the slots, the default image can easily be copied back if yo
 To program the Sonata bitstream:
 
 1. Download `lowrisc_sonata_system_0.bit` from THEBESTURL.COM/lowrisc_sonata_system_0.bit
-2. Select slot 2 using switch SW7 (`Bitstream`)
+2. Select slot 2 using switch SW3 (`Bitstream`)
 3. Plug in Sonata board. You should see a SONATA drive (see troubleshooting section if unsure).
 4. Drag the updated `.bit` file and wait for the copy to complete (on Linux note the copy command may return immediately, so you need to wait until it's done.)
 5. The board should automatically restart once the image is copied over. You should see the `FPGA Config` LED come on: