leds_dump() printed the pin mux, the LED enables and every LED set on each
boot, from BANK2. It now lives in its own file in BANK3, where there is
room, and runs only on the new "leds" command, next to gpio and sds, so it
stays at hand for bringing up a new board without costing BANK2 or boot
output.
Building with SDCC 4.6.0 emits tons of warnings e.g.:
cmd_parser.c:31: warning 356: object in read-only code space should be const
cmd_parser.c:36: warning 357: pointer to object in read-only code space should be pointer to const
These of course become fatal when building with --Werror.
Comparing resultant binaries, it seems that a single string is shifted
(deduplication?) but the numbers emitted at the end of the build are
otherwise identical.
leds_setup() walks all four LED sets and writes the high-speed nibble of
each into one of two registers, LED3_0_SET1 for sets 0 and 1 and
LED3_0_SET3 for sets 2 and 3. The second branch reuses the index
expression of the first without rebasing it, so sets 2 and 3 address
sfr_data[-1], [-2], [-3] and [-4].
Two things follow. Sets 2 and 3 never receive their nibble, because the
read-modify-write pair writes back exactly what it read. And four bytes
below sfr_data are overwritten on every boot of every machine: the loop
runs over all four sets whatever the board declares. On this build the
linker places sfr_data directly after the serial receive ring, so the
writes land in the tail of that ring.
leds_dump() reads the same two registers back and already rebases with
(set - 2); use the same form here.
DrDoof
Matt Merhar
bloqaudio
logicog
René van Dorst