ATM Pace Control
MPC885 PowerQUICC Family Reference Manual, Rev. 2
Freescale Semiconductor
40-11
Figure 40-4. Example of Single PHY and Single Serial APC Configuration
Multi-PHY scheduling works in the same way as the scheduling process described above. Each PHY can
support a different bit rate which is derived from the same APC timer basic rate. In this way, up to
thirty-four different APCs (Up to 31multi-PHY and three serial mode SARs) can be supported. Upon an
APC timer timeout, the CP begins servicing the serial APCs and then services multi-PHY31 through
multi-PHY0. Priority polling or round robin polling on the UTOPIA bus can be selected in UTMODE. The
servicing order for serial APCs is defined by APCST[NSER]. Figure 40-5. shows the MPC885 configured
with four multi-PHY SARs and three serial mode SARs.
Figure 40-5. Example of Maximum Multi-PHY and Multi-Serial APC Configuration
40.4
Using the APC Without Using SCC4 or UTOPIA
As described in
Section 40.3, “Using the APC with Multiple ATM Ports,”
the APC algorithm begins and
terminates by referring to the APCST parameter on parameter page 4. Therefore, the APCST parameter
on parameter page 4 must always be valid, even if the controllers associated with parameter page 4 (that
is, SCC4 or the UTOPIA port) are not used in ATM mode.
APC Timer
NSER4
APC1
NSER1
Page1
N timer
Page4
N timer
timeout
expire
request
APC2
expire
request
APC Timer
Page1
APC1
NSER4
APC2
APC3
NSER2
NSER1
NSER3
APC4
APC5
APC6
APC7
N timer
Page2
N timer
Page3
N timer
Page4
N timer
MPHY 0
Page4
N timer
MPHY 1
Page4
N timer
MPHY 2
Page4
N timer
MPHY 3
timeout
expire
request
expire
request
expire
request
expire
request
expire
request
expire
request
expire
request
Summary of Contents for PowerQUICC MPC870
Page 98: ...MPC885 PowerQUICC Family Reference Manual Rev 2 I 4 Freescale Semiconductor ...
Page 118: ...MPC885 Overview MPC885 PowerQUICC Family Reference Manual Rev 2 1 20 Freescale Semiconductor ...
Page 158: ...The MPC8xx Core MPC885 PowerQUICC Family Reference Manual Rev 2 3 18 Freescale Semiconductor ...
Page 288: ...MPC885 PowerQUICC Family Reference Manual Rev 2 III 4 Freescale Semiconductor ...
Page 554: ...MPC885 PowerQUICC Family Reference Manual Rev 2 V 6 Freescale Semiconductor ...
Page 1090: ...UTOPIA Interface MPC885 PowerQUICC Family Reference Manual Rev 2 43 8 Freescale Semiconductor ...
Page 1312: ...Byte Ordering MPC885 PowerQUICC Family Reference Manual Rev 2 A 8 Freescale Semiconductor ...
Page 1336: ...MPC885 PowerQUICC Family Reference Manual Rev 2 D 16 Freescale Semiconductor ...
Page 1358: ...MPC885 PowerQUICC Family Reference Manual Rev 2 D 38 Freescale Semiconductor ...
Page 1370: ...MPC880 MPC885 PowerQUICC Family Reference Manual Rev 2 E 4 Freescale Semiconductor ...
Page 1386: ...Revision History MPC885 PowerQUICC Family Reference Manual Rev 2 I 2 Freescale Semiconductor ...