HD6417618 RENESAS [Renesas Technology Corp], HD6417618 Datasheet - Page 345

• Manufacturer Part Number: HD6417618
• Description: 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7618 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Figure 12.13 Countermeasure for the Case with TC Interrupt-Driven Software: Addition of
Notes: 1. The specified constant period is the timeout period mentioned in section 12.4.1, Usage Notes on SH-Ether EtherC/E-DMAC Status Register
1.
2.
3.
4.
5.
Timeout Processing within the Limit Imposed by the Maximum Specified Time
2. Set n with reference to the maximum specified time values in table 12.2.
After setting the corresponding transmit
descriptor, set the TR bit in EDTRR to 1.
: Processing added as the countermeasure for the problem
Prepare multiple transmit descriptors.
After setting the transmit descriptor,
set the TR bit in EDTRR to 1.
(EESR).
Read the TACT bit of the
corresponding transmit descriptor.
Transmission task
Next transmission task
generated?
Transmission starts.
TACT = 0?
Yes
Yes
Section 12 Ethernet Controller Direct Memory Access Controller (E-DMAC)
No
No
4.
Call an OS service routine with
a timeout function to place the
transmission task in a waiting state.
End
Has the transmission task
left the waiting state within
he constant specified time?
i = 0;
Yes
7.
5.
6.
Read the TACT bit of the
corresponding transmit
descriptor.
*
1
TACT = 0?
Timeout
No
i < n?
i++;
Rev. 6.00 Jun. 12, 2007 Page 313 of 610
Yes
Yes
*
2
Make an OS service call to bring the
transmission task out of the waiting state.
Generation of EtherC/E-DMAC
interrupt
Save EESR and clear the bit
by writing 1.
Interrupt processing for interrupts
other than TC
Interrupt other than TC?
8.
No
No
Interrupt handler
Make initial settings of the
EtherC and E-DMAC modules.
Initialize the transmit/receive
descriptors and transmit/receive
buffers.
Issue a software reset to
initialize the EtherC and
E-DMAC modules.
TC interrupt?
End
Yes
Yes
REJ09B0131-0600
No
No