USBN9603 National Semiconductor, USBN9603 Datasheet - Page 31

• Manufacturer Part Number: USBN9603
• Description: USBN9603 Universal Serial Bus Full Speed Function Controller with Enhanced DMA Support
• Manufacturer: National Semiconductor

7.0 Register Set
7.1.2
CLKDIV
External Clock Divisor. A hardware reset configures the divisor to 11
at the CLKOUT pin.
If the CLKDIV value is changed by firmware, the clock output is expanded/shortened if the CLKDIV value is increased/de-
creased in its current phase to allow glitch-free switching.
CODIS
Clock Output Disable. Setting this bit disables the clock output. The CLKOUT pin is frozen in its current state and resumes
with a new period when this bit is cleared.
7.1.3
This register holds the binary encoded chip revision.
REVID
Revision Identification. For this revision, 9603 Rev A, the field contains 0010
Clock Configuration Register (CCONF)
Revision Identifier (RID)
frequency = 48 MHz / (CLKDIV+1)
CODIS
bit 7
bit 7
r/w
0
(Continued)
bit 6
bit 6
Reserved
-
-
Reserved
1
0
0
1
1
INTOC
Table 5. Interrupt Output Control Bits
bit 5
bit 5
-
-
0
0
1
0
1
Disabled
Active low open drain
Active high push-pull
Active low push-pull
bit 4
bit 4
31
Interrupt Output
bit 3
bit 3
1
0
d
(decimal format), which yields a 4 MHz output clock
b
bit 2
bit 2
.
0
0
CLKDIV3-0
REVID3-0
r/w
r
bit 1
bit 1
1
1
bit 0
bit 0
1
0
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