dp83251 National Semiconductor Corporation, dp83251 Datasheet - Page 50

• Manufacturer Part Number: dp83251
• Description: Player Device Fddi Physical Layer Controller
• Manufacturer: National Semiconductor Corporation

5 0 Registers
CURRENT INJECTION COUNT REGISTER (CIJCR)
The Current Injection Count Register takes a snap-shot of the Injection Counter during every Control Bus Interface read-cycle of
this register
During a Control Bus Interface write-cycle the PLAYER device will set the Control Bus Write Command Reject bit (CCR) of the
Interrupt Condition Register (ICR) to 1 and will ignore a write-cycle
The Injection Counter is an 8-bit down-counter which decrements every 80 ns
The counter is active only during One Shot or Periodic Injection Modes (i e Injection Control
Current Transmit State Register (CTSR) are set to either 01 or 10)
The Injection Threshold Register (IJTR) value is loaded into the Injection Counter when the counter reaches zero and during
every Control Bus Interface write-cycle of IJTR
The counter is initialized to 0 during the reset process (i e RST
ACCESS RULES
D0
D1 – 6
D7
D7
IJC7
ADDRESS
Bit
19h
D6
IJC6
(Continued)
IJC0
IJC1 – 6
IJC7
READ
Always
Symbol
D5
IJC5
WRITE
Write Reject
D4
IJC4
INJECTION COUNT BIT
of the Injection Counter
INJECTION COUNT BIT
value of the Injection Counter
INJECTION COUNT BIT
value of the Injection Counter
D3
IJC3
50
e
GND)
D2
IJC2
k
k
k
0
1 – 6
7
l
l
l
Least significant bit (LSB) of the current value
Most significant bit (MSB) of the current
Description
Intermediate bits representing the current
D1
IJC1
k
D0
IJC0
1 0
l
bits (IC
k
1 0
l
) of the