MC68HC912B32VFU8 Freescale Semiconductor, MC68HC912B32VFU8 Datasheet - Page 80

• Manufacturer Part Number: MC68HC912B32VFU8
• Manufacturer: Freescale Semiconductor

Specifications of MC68HC912B32VFU8

• Cpu Family: HC12
• Device Core Size: 16b
• Frequency (max): 8MHz
• Interface Type: SCI/SPI
• Program Memory Type: EPROM
• Program Memory Size: 32KB
• Total Internal Ram Size: 1KB
• # I/os (max): 63
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 4.5V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 105C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 80
• Package Type: PQFP
• Lead Free Status / Rohs Status: Not Compliant

Operating Modes and Resource Mapping
5.4.2 Register Initialization Register
After reset, the 512-byte register block resides at location $0000 but can be reassigned to any 2-Kbyte
boundary within the standard 64-Kbyte address space. Mapping of internal registers is controlled by five
bits in the register initialization register (INITRG). The register block occupies the first 512 bytes of the
2-Kbyte block.
Read: Anytime
Write: Once in normal modes; anytime in special modes
REG15–REG11 — Register Position Bits
MMSWAI — Memory Mapping Interface Stop in Wait Control Bit
5.4.3 RAM Initialization Register
After reset, addresses of the 1-Kbyte RAM array begin at location $0800 but can be assigned to any
2-Kbyte boundary within the standard 64-Kbyte address space. Mapping of internal RAM is controlled by
five bits in the RAM initialization register (INITRM). The RAM array occupies the first 1 Kbyte of the
2-Kbyte block.
Read: Anytime
Write: Once in normal modes; anytime in special modes
RAM15–RAM11 — RAM Position Bits
80
These bits specify the upper five bits of the 16-bit register address.
This bit controls access to the memory mapping interface when in wait mode.
Normal modes: Write anytime
Special modes: Write never
These bits specify the upper five bits of the 16-bit RAM address.
0 = Memory mapping interface continues to function in wait mode.
1 = Memory mapping interface access shuts down in wait mode.
Address: $0011
Reset:
Read:
Write:
Address: $0010
Reset:
Read:
Write:
REG15
Bit 7
RAM15
0
Bit 7
0
Figure 5-2. Register Initialization Register (INITRG)
Figure 5-3. RAM Initialization Register (INITRM)
REG14
RAM14
6
0
6
0
M68HC12B Family Data Sheet, Rev. 9.1
REG13
RAM13
5
0
5
0
REG12
RAM12
4
0
4
0
RAM11
REG11
3
1
3
0
2
0
0
2
0
0
1
0
0
1
0
0
Freescale Semiconductor
Bit 0
MMSWAI
0
0
Bit 0
0