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SPI SD-Card: setup valid CRC-7 for STOP_TRANSMISSION command.

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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
same cards types 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 <ppisa@pikron.com>
This commit is contained in:
Pavel Pisa
2013-10-08 10:40:29 +02:00
committed by Sebastian Huber
parent 7c709c05e9
commit df29cfeb0c
1 changed files with 5 additions and 0 deletions
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5
c/src/libchip/i2c/spi-sd-card.c
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@@ -501,8 +501,13 @@ 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);*/
crc7 = 0x30; /* Help compiler - command and argument are constants */
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");