On 2013-10-04 09:34, Pavel Pisa wrote:
From: Pavel Pisa <pp...@pikron.com>STOP_TRANSMISSION command is used to finish READ_MULTIPLE_BLOCK command and its format is regular command format. It requires valid CRC-7 to have effect at least on some card brands else it is ignored and attempt to issue next READ or WRITE commands results in illegal command condition (0x04) preceded by strange (0x3f) for tested card. Signed-off-by: Pavel Pisa <pp...@pikron.com> --- c/src/libchip/i2c/spi-sd-card.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/c/src/libchip/i2c/spi-sd-card.c b/c/src/libchip/i2c/spi-sd-card.c index 5a30451..89d5fb5 100644 --- a/c/src/libchip/i2c/spi-sd-card.c +++ b/c/src/libchip/i2c/spi-sd-card.c @@ -501,8 +501,12 @@ static int sd_card_send_register_command( sd_card_driver_entry *e, uint32_t comm static int sd_card_stop_multiple_block_read( sd_card_driver_entry *e) { int rv = 0; + uint8_t crc7; SD_CARD_COMMAND_SET_COMMAND( e->command, SD_CARD_CMD_STOP_TRANSMISSION); + SD_CARD_COMMAND_SET_ARGUMENT( e->command, 0); + crc7 = sd_card_compute_crc7( e->command + 1, 5); + SD_CARD_COMMAND_SET_CRC7( e->command, crc7); rv = rtems_libi2c_write_bytes( e->bus, e->command, SD_CARD_COMMAND_SIZE); RTEMS_CHECK_RV( rv, "Write stop transfer token");
Since the command uses only constants is it sufficient to use SD_CARD_COMMAND_SET_ARGUMENT( e->command, 0); SD_CARD_COMMAND_SET_CRC7( e->command, 0x7a); ? -- Sebastian Huber, embedded brains GmbH Address : Dornierstr. 4, D-82178 Puchheim, Germany Phone : +49 89 189 47 41-16 Fax : +49 89 189 47 41-09 E-Mail : sebastian.hu...@embedded-brains.de PGP : Public key available on request. Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG. _______________________________________________ rtems-devel mailing list rtems-devel@rtems.org http://www.rtems.org/mailman/listinfo/rtems-devel
