Des/3Des Input/Output Data Fifo Register - Samsung S3C2500B User Manual

S3C2500B

11.3.9 DES/3DES INPUT/OUTPUT DATA FIFO REGISTER

Bit Number
[31:0] DESINFIFO
Bit Number
[31:0] DESOUTFIFO
Table 11-14. DES/3DES Input Data FIFO Description
Bit Name
This FIFO can be filled by CPU or DMA (depends on control register
value). This FIFO consists of 8 words. If data are transferred by
DMA the 4-word burst transaction (DESCON[7] is zero, and
DCON#[5] is one) is recommended. Otherwise, if data are
transferred by CPU, the 2-word transaction (DESCON[7] is one) is
recommended.
If DESCON[3] is zero, the 1
be encrypted/decrypted, bit[1:32]. The second one is the right half of
data to be encrypted/decrypted, bit[33:64]. Otherwise, if
DESCON[3] is one, the 1
encrypted/decrypted, bit[33:64]. The second one is the left half of
data to be encrypted/decrypted, bit[1:32].
The byte order in the DESINFIFO is LSB first. That is, the LSB byte
is stored to DESINFIFO[31:24]. If you need to swap the byte order,
you can control it by using DESCON[10]. If DESCON[10] is set, the
written data to the DESINFIFO is automatically byte-swapped.
Otherwise, the written data have the original byte order.
Table 11-15. DES/3DES Output Data FIFO Description
Bit Name
This FIFO can be read by CPU or DMA (depends on control register
value). This FIFO consists of 8 words. If data are transferred by
DMA the 4-word burst transaction (DESCON[7] is zero, and
DCON#[5] is one) is recommended. Otherwise, if data are
transferred by CPU, the 2-word transaction (DESCON[7] is one) is
recommended.
If DESCON[3] is zero, the 1
encrypted/decrypted, bit[1:32]. The second one is the right half of
data encrypted/decrypted, bit[33:64]. Otherwise, if DESCON[3] is
one, the 1
bit[33:64]. The second one is the left half of data
encrypted/decrypted, bit[1:32].
The byte order in the DESOUTFIFO is LSB first. That is the LSB
byte is read from DESOUTFIFO[31:24]. If you need to swap the
byte order, you can control it by using DESCON[10]. If
DESCON[10] is set, the read data from the DESOUTFIFO is
automatically byte-swapped. Otherwise, the read data have the
original byte order.
Description
st
written data is the left half of data to
st
written data is the right half of data to be
Description
st
read data is the left half of data
st
read data is the right half of data encrypted/decrypted,
DES/3DES
11-9