EMAC Control Module Registers
1865
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
EMAC/MDIO Module
32.3.12 EMAC Control Module Receive Interrupts Per Millisecond Registers (C0RXIMAX)
The EMAC control module receive interrupts per millisecond register (C0RXIMAX) is shown in
and described in
Figure 32-26. EMAC Control Module Receive Interrupts Per Millisecond Register (C0RXIMAX)
(offset = 70h)
31
16
Reserved
R-0
15
6
5
0
Reserved
RXIMAX
R-0
R/W-0
LEGEND: R = Read only; R/W = Read/Write; -
n
= value after reset
Table 32-22. EMAC Control Module Receive Interrupts Per Millisecond Register (C0RXIMAX)
Bit
Field
Value
Description
31-6
Reserved
0
Reserved
5-0
RXIMAX
2-3Fh
RXIMAX is the desired number of C0RXPULSE interrupts generated per millisecond when
C0RXPACEEN is enabled in INTCONTROL.
The pacing mechanism can be described by the following pseudo-code:
while(1) {
interrupt_count = 0;
/* Count interrupts over a 1ms window */
for(i = 0; i < INTCONTROL[INTPRESCALE]*250; i++) {
interrupt= NEW_INTERRUPT_EVENTS();
if(i < INTCONTROL[INTPRESCALE]*pace_counter)
BLOCK_EMAC_INTERRUPTS();
else
ALLOW_EMAC_INTERRUPTS();
}
ALLOW_EMAC_INTERRUPTS();
if(interrupt_count > 2*RXIMAX)
pace_counter = 255;
else if(interrupt_count > 1.5*RXIMAX)
pace_counter = previous_pace_counter*2 + 1;
else if(interrupt_count > 1.0*RXIMAX)
pace_counter = previous_pace_c 1;
else if(interrupt_count > 0.5*RXIMAX)
pace_counter = previous_pace_counter - 1;
else if(interrupt_count != 0)
pace_counter = previous_pace_counter/2;
else
pace_counter = 0;
previous_pace_counter = pace_counter;
}