Datasheet

Functional Description
MC13783 Technical Data, Rev. 3.5
Freescale Semiconductor 43
Figure 11. USB/RS232 Transceiver Data Flow
Upon a USB legacy host detection, an interrupt is generated but neither the transceiver nor the VUSB
regulator are automatically enabled. This must be done by software before data transmission. The
transceiver can also be enabled during boot mode.
Via SPI bits DATSE0 and BIDIR, one of the four USB operating modes can be selected. However, when
starting up in a boot mode, there is no up front SPI programming possible. The default operating mode is
then determined by the setting of the UMOD pin as indicated in Table 26.
UDATVP
USE0VM
UTXENB
UDP
UDM
URXVM
URCVD
URXVP
R
x
Dif
f
TO ACCESSORY
CONNECTOR
TO PROCESSOR
SEO
Tx
R
x
Router
DATSEO, BIDIR