echoplayer: re-enable 50 MHZ SDMMC bus
rockbox-gerrit-noreply--- via rockbox-cvs <[email protected]>
| Newsgroups | gmane.comp.systems.archos.rockbox.cvs |
|---|---|
| Message-ID | <[email protected]> |
commit e5e82820f64cd3a3075260af3a5fc6e9006d5afe Author: Aidan MacDonald <[email protected]> Date: Sun Feb 15 21:14:41 2026 +0000 echoplayer: re-enable 50 MHZ SDMMC bus The problem with drive strength and things not working reliably at 50 MHz turned out to be entirely caused by the ESD diodes on the data/command/clock lines, which have a whopping 200-300 pF junction capacitance -- 6-10x higher than the 30 pF limit given by the MMC spec. After desoldering the diodes the bus seems stable at 50 MHz and with any drive strength (note MEDIUM is still fast enough even for 50 MHz, so the drive strength is unchanged). Change-Id: If9847ee4145f5ed2f7e172cfa89acad0737a897f diff --git a/firmware/target/arm/stm32/echoplayer/sdmmc-echoplayer.c b/firmware/target/arm/stm32/echoplayer/sdmmc-echoplayer.c index 3b3b860680..803b7cae2b 100644 --- a/firmware/target/arm/stm32/echoplayer/sdmmc-echoplayer.c +++ b/firmware/target/arm/stm32/echoplayer/sdmmc-echoplayer.c @@ -46,7 +46,8 @@ static const struct sdmmc_host_config sdmmc_config INITDATA_ATTR = { .bus_widths = SDMMC_BUS_WIDTH_1BIT | SDMMC_BUS_WIDTH_4BIT, .bus_clocks = SDMMC_BUS_CLOCK_400KHZ | - SDMMC_BUS_CLOCK_25MHZ, + SDMMC_BUS_CLOCK_25MHZ | + SDMMC_BUS_CLOCK_50MHZ, .max_nr_blocks = 65535, .is_removable = true, }; -- rockbox-cvs mailing list [email protected] https://lists.haxx.se/mailman/listinfo/rockbox-cvs