MC3S12RG128 Datasheet, PDF (149/546 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 4 Multiplexed External Bus Interface (MEBIV3) Block Description
Table 4-7. MODC, MODB, and MODA Write Capability¹
MODC MODB MODA
Mode
MODx Write Capability
0
0
0
Special single chip
MODC, MODB, and MODA
write anytime but not to 110²
0
0
1
Emulation narrow
No write
0
1
0
Special test
MODC, MODB, and MODA
write anytime but not to 110⁽²⁾
0
1
1
Emulation wide
No write
1
0
0
Normal single chip
MODC write never,
MODB and MODA write once
but not to 110
1
0
1
Normal expanded narrow
No write
1
1
0
Special peripheral
No write
1
1
1
Normal expanded wide
No write
1 _{No writes to the MOD bits are allowed while operating in a secure mode. For more details, refer to the device overview chapter.}
2 _{If you are in a special single-chip or special test mode and you write to this register, changing to normal single-chip mode, then}
one allowed write to this register remains. If you write to normal expanded or emulation mode, then no writes remain.
4.3.2.10 Pull-Up Control Register (PUCR)
Module Base + 0x000C
Starting address location affected by INITRG register setting.
7
6
R
0
PUPKE
W
Reset¹
1
0
5
4
3
0
0
PUPEE
0
1
0
2
1
0
0
PUPBE
PUPAE
0
0
0
NOTES:
1. The default value of this parameter is shown. Please refer to the device overview chapter to determine the actual
reset state of this register.
= Unimplemented or Reserved
Figure 4-15. Pullup Control Register (PUCR)
Read: Anytime (provided this register is in the map).
Write: Anytime (provided this register is in the map).
This register is used to select pull resistors for the pins associated with the core ports. Pull resistors are
assigned on a per-port basis and apply to any pin in the corresponding port that is currently configured as
an input. The polarity of these pull resistors is determined by chip integration. Please refer to the device
overview chapter to determine the polarity of these resistors.
MC3S12RG128 Data Sheet, Rev. 1.05
Freescale Semiconductor
149