Siemens C541U, User Manual

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Semiconductor Group 6-82 1999-04-01
On-Chip Peripheral Components
C541U
USB Module Data Register USBDRn, n=0..7 (Address E8H - EFH)
It is recommended to arrange the data by writing USBDR0 with the first byte. For the rest of the data,
put the last byte in USBDR1 and the second last byte (if any) in USBDR2, the third last byte (if any)
in USBDR3 and so on, until the second byte. So if the length of data is
n , i.e. data[0], data[1], ...
data[ n -2], data[ n -1], then the data should be arranged in the following manner:
USBDR0 <- data[0]
USBDR1 <- data[
n
-1]
USBDR2 <- data[
n
-2]
...
USBDR
n
-1 <- data[1]
MSB
LSB
USBDR3
7 6 5 4 3 2 1 0
Bit No.
rw
rw rw rw
.2 .1 .0
USBDR0
USBDR1
USBDR2
E8H
E9H
EAH
EBH
.7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
rw
rw rw rw
.2 .1 .0 .7 .6 .5 .4 .3
rw rw rw rw
USBDR7
USBDR4
USBDR5
USBDR6
ECH
EDH
EEH
EFH