Freescale Semiconductor HCS08 Series, Reference Manual

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Universal Serial Bus Device Controller (S08USBV1)
MC9S08JS16 MCU Series Reference Manual, Rev. 4
Freescale Semiconductor 257
15.3.11 Address Register (ADDR)
The ADDR register contains the unique 7-bit address the device will be recognized as through USB. The
register is reset to 0x00 after the reset input has gone active or the USB module has decoded USB reset
signaling. That will initialize the address register to decode address 0x00 as required by the USB
specification. Firmware will change the value when it processes a SET_ADDRESS request.
15.3.12 Frame Number Register (FRMNUML, FRMNUMH)
The frame number registers contains the 11-bit frame number. The frame number registers require two
8-bit registers to implement. The low order byte is contained in FRMNUML, and the high order byte is
contained in FRMNUMH. These registers are updated with the current frame number whenever a SOF
TOKEN is received.
7 6 5 4 3 2 1 0
R 0
ADDR6 ADDR5 ADDR4 ADDR3 ADDR2 ADDR1 ADDR0
W
Reset 0 0 0 0 0 0 0 0
Figure 15-14. Address Register (ADDR)
Table 15-14. ADDR Field Descriptions
Field Description
6–0
ADDR[6:0]
USB Address — This 7-bit value defines the USB address that the USB module will decode
7 6 5 4 3 2 1 0
R FRM7 FRM6 FRM5 FRM4 FRM3 FRM2 FRM1 FRM0
W
Reset 0 0 0 0 0 0 0 0
= Unimplemented or Reserved
Figure 15-15. Frame Number Register Low (FRMNUML)
Table 15-15. FRMNUML Field Descriptions
Field Description
7–0
FRM[7:0]
Frame Number — These bits represent the low order bits of the 11 bit frame number.