[PATCH 10/15] doc: Add a note about number representation

Simon Glass
2021-07-20T13:32:02Z

Mention the default base of U-Boot in the command-line section. Add
examples for decimal and octal.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

doc/usage/cmdline.rst | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)

diff --git a/doc/usage/cmdline.rst b/doc/usage/cmdline.rst
index c7008d646c9..5df38f18c56 100644
--- a/doc/usage/cmdline.rst
+++ b/doc/usage/cmdline.rst
@@ -52,3 +52,34 @@ General rules
calling run with a list of variables as arguments), any failing
command will cause "run" to terminate, i. e. the remaining
variables are not executed.
+
+Representing numbers
+--------------------
+
+Most U-Boot commands use hexadecimal (hex) as the default base, for convenient
+use of addresses, for example::
+
+ => md 1000 6
+ 00001000: 2c786f62 00697073 03000000 0c000000 box,spi.........
+ 00001010: 67020000 00000000 ...g....
+
+There is no need to add a `0x` prefix to the arguments and the output is shown
+in hex also, without any prefixes. This helps to avoid clutter.
+
+Some commands use decimal where it is more natural::
+
+ => i2c dev 0
+ Setting bus to 0
+ => i2c speed
+ Current bus speed=400000
+ => i2c speed 100000
+ Setting bus speed to 100000 Hz
+
+In some cases the default is decimal but it is possible to use octal if that is
+useful::
+
+ pmic dev pmic@41
+ dev: 1 @ pmic@41
+ => pmic write 2 0177
+ => pmic read 2
+ 0x02: 0x00007f
--
2.32.0.402.g57bb445576-goog