Texas Instruments AM335 Series Technical Reference Manual

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18.5.1.22 SD_AC12 Register (offset = 23Ch) [reset = 0h]
SD_AC12 is shown in Figure 18-58 and described in Table 18-41.
The host driver may determine which of the errors cases related to Auto CMD12 has occurred by checking
this SD_AC12 register when an auto CMD12 error interrupt occurs. This register is valid only when auto
CMD12 is enabled (SD_CMD[2] ACEN bit) and auto CMD12Error (SD_STAT[24] ACE bit) is set to 1.
These bits are automatically reset when starting a new adtc command with data.
Figure 18-58. SD_AC12 Register
31 30 29 28 27 26 25 24
Reserved
R-0h
23 22 21 20 19 18 17 16
Reserved
R-0h
15 14 13 12 11 10 9 8
Reserved
R-0h
7 6 5 4 3 2 1 0
CNI Reserved ACIE ACEB ACCE ACTO ACNE
R-0h R-0h R-0h R-0h R-0h R-0h R-0h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 18-41. SD_AC12 Register Field Descriptions
Bit Field Type Reset Description
31-8 Reserved R 0h
7 CNI R 0h Command not issue by auto CMD12 error.
If this bit is set to 1, it means that pending command is not executed
due to auto CMD12 error ACEB, ACCE, ACTO, or ACNE.
0x0 = Not error
0x1 = Command not issued
6-5 Reserved R 0h
4 ACIE R 0h Auto CMD12 index error.
This bit is a set to 1 when response index differs from corresponding
command auto CMD12 index previously emitted.
This bit depends on the command index check enable (SD_CMD[20]
CICE bit).
0x0 = No error
0x1 = Auto CMD12 index error
3 ACEB R 0h Auto CMD12 end bit error.
This bit is set to 1 when detecting a 0 at the end bit position of auto
CMD12 command response.
0x0 = No error
0x1 = AutoCMD12 end bit error
2 ACCE R 0h Auto CMD12 CRC error.
This bit is automatically set to 1 when a CRC7 error is detected in
the auto CMD12 command response depending on the enable in the
SD_CMD[19] CCCE bit.
0x0 = No error
0x1 = Auto CMD12 CRC error
1 ACTO R 0h Auto CMD12 timeout error.
This bit is set to 1 if no response is received within 64 clock cycles
from the end bit of the auto CMD12 command.
0x0 = No error
0x1 = Auto CMD12 time out
3435
SPRUH73H–October 2011–Revised April 2013 Multimedia Card (MMC)
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Texas Instruments AM335 Series Specifications

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Brand	Texas Instruments
Model	AM335 Series
Category	Computer Hardware
Language	English