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Figure ) – Rainbow Electronics AT89C5132 User Manual

Page 99

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99

AT8xC5132

4173A–8051–08/02

Table 95. MMCON1 Register

MMCON1 (S:E5h) – MMC Control Register 1

Reset Value = 0000 0000b

Table 96. MMCON2 Register

MMCON2 (S:E6h) – MMC Control Register 2

Reset Value = 0000 0000b

7

6

5

4

3

2

1

0

BLEN3

BLEN2

BLEN1

BLEN0

DATDIR

DATEN

RESPEN

CMDEN

Bit

Number

Bit

Mnemonic

Description

7 - 4

BLEN3:0

Block Length Bits
Refer to Table 93 for Bits description. Do not program value > 1011b.

3

DATDIR

Data Direction Bit
Set to select data transfer from host to card (write mode).
Clear to select data transfer from card to host (read mode).

2

DATEN

Data Transmission Enable Bit
Set and clear to enable data transmission immediately or after response has
been received.

1

RESPEN

Response Enable Bit
Set and clear to enable the reception of a response following a command
transmission.

0

CMDEN

Command Transmission Enable Bit
Set and clear to enable transmission of the command FIFO to the card.

7

6

5

4

3

2

1

0

MMCEN

DCR

CCR

-

-

DATD1

DATD0

FLOWC

Bit

Number

Bit

Mnemonic

Description

7

MMCEN

MMC Clock Enable Bit
Set to enable the MCLK clocks and activate the MMC controller.
Clear to disable the MMC clocks and freeze the MMC controller.

6

DCR

Data Controller Reset Bit
Set and clear to reset the data line controller in case of transfer abort.

5

CCR

Command Controller Reset Bit
Set and clear to reset the command line controller in case of transfer abort.

4 - 3

-

Reserved
The values read from these Bits are always 0. Do not set these Bits.

2 - 1

DATD1:0

Data Transmission Delay Bits

Used to delay the data transmission after a response from 2 MMC clock periods
(all Bits cleared) to 8 MMC clock periods (all Bits set) by step of 2 MMC clock
periods.

0

FLOWC

MMC Flow Control Bit
Set to enable the flow control during data transfers.
Clear to disable the flow control during data transfers.