PXD20 Datasheet, PDF (105/130 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

Electrical characteristics
4.18.2 Nexus debug interface
Table 53. Nexus debug port timing¹
Num
Symbol
C
Characteristic
Min
Max
Unit
SpecID
1
t_MCYC
CC² D MCKO Cycle Time
15
—
ns
A2.1
2
t_MDC
CC² D MCKO Duty Cycle
40
60
%
A2.2
3
t_MDOV
CC² D MCKO Low to MDO Data Valid³
0.1
0.2
t_MCYC
A2.3
4
t_MSEOV
CC² D MCKO Low to MSEO Data Valid³
0.1
0.2
t_MCYC
A2.4
5
t_EVTOV
CC² D MCKO Low to EVTO Data Valid³
0.1
0.2
t_MCYC
A2.5
6
t_EVTIPW
CC² D EVTI Pulse Width
4
—
t_TCYC
A2.6
7
t_EVTOPW
CC² D EVTO Pulse Width
1
—
t_MCYC
A2.7
8
t_TCYC
CC² D TCK Cycle Time⁴
100
—
ns
A2.8
9
t_TDC
CC² D TCK Duty Cycle
40
60
%
A2.9
10 t_NTDIS, t_NTMSS CC² D TDI, TMS Data Setup Time
25
—
ns
A2.10
11
t_NTDIH,
CC² D TDI, TMS Data Hold Time
t_NTMSH
5
—
ns
A2.11
12
t_JOV
CC² D TCK Low to TDO Data Valid
0
35
ns
A2.12
1 _{JTAG specifications in this table apply when used for debug functionality. All Nexus timing relative to MCKO is measured from}
50% of MCKO and 50% of the respective signal. Nexus timing specified at V_DD = 3.0 V to 3.6 V, T_A = –40 to 105 °C, and
CL = 50 pF (Cl = 30 pF on MCKO), with SRC = 0b10 for MCKO and 0b11 for others.
2 _{Parameter values guaranteed by design.}
3 _{MDO, MSEO, and EVTO data is held valid until next MCKO low cycle.}
4 _{The system clock frequency needs to be three times faster that the TCK frequency.}
Nexus Dual Data Rate is not supported. The timings are mentioned for dedicated pins on 416TEPBGA package. The max value
for #2, 3, and 4 above, are 0.3 of tMCYC for shared Nexus ports.
MCKO
MDO
MSEO
EVTO
1
2
3
4
5
Output Data Valid
Figure 21. Nexus output timing
PXD20 Microcontroller Data Sheet, Rev. 2
Freescale Semiconductor
Preliminary—Subject to Change Without Notice
105