ST7267C8 ST7267R8
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USB INTERFACE (Cont’d)
FRAME NUMBER REGISTER MSB (FRNBRM)
Read Only.
Reset value: 0000 0000 (00h)
This register indicates the MSB of the last frame
number received.
Bit 7:3 = Reserved.
Bit 2:0 = FN[10:8] Frame number MSB.
FRAME NUMBER REGISTER LSB (FRNBRL)
Read Only.
Reset value: 0000 0000 (00h)
This register indicates the LSB of the last frame
number received.
Bit 7:0 = FN[7:0] Frame number LSB.
TEST MODE REGISTER (TSTMODER)
Read/Write
Reset value: 0000 0000(00h)
This register is used to put the USB device into
one of the four test modes described in the
USB 2.0 specification. It is not used in normal op-
eration.
Bit 7:6 = Reserved.
Bit 5 = FFS Force Full-Speed.
Software can set this bit to force the USB device
into Full-speed mode when it receives a USB re-
set.
Bit4 = FHS Force High-Speed.
Software can set this bit to force the USB device
into High-speed mode when it receives a USB re-
set.
Bit 3 = TPAK Test Packet.
Software can set this bit to enter the Test_Packet
test mode. In this mode, the USB device– in high-
speed mode – repetitively transmits on the bus a
53-byte test packet.
Note: The 53-byte test packet must be loaded into
the Endpoint 0 FIFO before the test mode is en-
tered.
Bit 2 = TK Test K.
Software can set this bit to enter the Test_K test
mode. In this mode, the USB device– in high-
speed mode – transmits a continuous K on the
bus.
Bits 1 = TJ Test J.
Software can set this bit to enter the Test_J test
mode. In this mode, the MUSBHSFC – in high-
speed mode – transmits a continuous J on the
bus.
Bits 0= TSE0N Test SE0 NAK.
Software
can
set
this
bit
to
enter
the
Test_SE0_NAK test mode. In this mode, the USB
Device remains in high-speed mode and responds
to any valid IN token with a NAK.
INDEX REGISTER (INDEXR)
Read/Write
Reset value: 0000 0000 (00h)
This register is written by software to determine
which endpoint control/status registers are ad-
dressed at 10h to 19h.
Bits [7:2] = Reserved.
Bit 1:0= IND[1:0] Index.
70
0000
0
FN10
FN9
FN8
70
FN7
FN6
FN5
FN4
FN3
FN2
FN1
FN0
70
0
FFS
FHS
TPAK
TK
TJ
TSE0N
70
00
IND1
IND0