RM0029 Datasheet, PDF (1685/1740 Pages) STMicroelectronics – The primary objective of this document

RM0029
Nexus Port Controller (NPC)
● As some of the pads used for the Nexus interface are multi-voltage pads, the maximum
supported interface frequency is limited to 40 MHz in some modes. This corresponds
to a MCKO clock divider of 1/2 for system clocks up to 80 MHz, and 1/4 for system
clocks > 80 MHz.
● Nexus Double Data Rate (DDR) mode is not available in the SPC564A74xx,
SPC564A80xx family of devices.
● A control bit in the Nexus port controller, NP_PCR[NEXCFG], is used to control
whether the added signals for full width trace port are routed to the MDO[4:11] signals,
or the CAL_MDO[4:11] signals. Although the CAL_MDO[4:11] signals are only
available in the 496 CSP package, this control bit still needs to be programmed when
the device is assembled in any other package.
Table 943 shows the maximum trace port frequencies supported in different
configurations, as well as the operation of the NPC_PCR[FPM] and [NEXCFG] control
bits.
Table 943. Nexus trace port routing and speed
Package
Production
(176QFP,
208BGA,
324BGA)
Debug/Cal
package
(496 CSP)
Max.
trace
port
MHz
Port width
Port routing bit MDO[0:3] MDO[4:11] CAL_MDO[4:11]
NPC_PCR[FPM] NPC_PCR[NEXCFG] usage
usage
usage
4 MDO
80
Don’t care
(Narrow, FPM=0)
12 MDO
40
(Wide, FPM=1)
NEXCFG = 1
4 MDO
80
Don't care
(Narrow, FPM=0)
40
12 MDO
(Wide, FPM=1)
80
NEXCFG = 1
Use MDO
NEXCFG = 0
(Default setting)
Use CAL_MDO
I/O use
Trace port
use
Inactive
Trace port
use
I/O use
Trace port
use
Trace port use
I/O use
Trace port use
37.1.2 Parameter values
Table 944. Parameter values
Parameter
Description
RPM_MDO (R)
NUM_AUX (X)
NUM_BKPT (B)
NUM_EVTO (E)
NPC parameters
Number of MDO pins available in reduced-port mode
Number of Nexus devices on the device sharing the Nexus
auxiliary port (not including the NPC)
Number of breakpoint requests coming into the block from
Nexus and non-Nexus sources on the device
Number of sources that output an EVTO
Value
4
1
1
2
Doc ID 15177 Rev 8
1685/1740