MC812A4CPVE8 Freescale Semiconductor, MC812A4CPVE8 Datasheet - Page 79

• Manufacturer Part Number: MC812A4CPVE8
• Description: IC MCU 16BIT EEPROM 4K 112-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HC12r

Specifications of MC812A4CPVE8

• Core Processor: CPU12
• Core Size: 16-Bit
• Speed: 8MHz
• Connectivity: SCI, SPI
• Peripherals: POR, WDT
• Number Of I /o: 83
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: EEPROM
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 112-LQFP
• Processor Series: HC812A
• Core: HC12
• Data Bus Width: 16 bit
• Data Ram Size: 1 KB
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 91
• Number Of Timers: 8
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 8 Channel
• Controller Family/series: 68HC12
• No. Of I/o's: 91
• Eeprom Memory Size: 4KB
• Ram Memory Size: 1KB
• Cpu Speed: 8MHz
• No. Of Timers: 1
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

Chapter 8
Memory Expansion and Chip-Select
8.1 Introduction
To use memory expansion, the MCU must be operated in one of the expanded modes. Sections of the
standard 64-Kbyte address space have memory expansion windows which allow an external address
space larger than 64 Kbytes. Memory expansion consists of three memory expansion windows and six
address lines which are used in addition to the standard 16 address lines.
The memory expansion function reuses as many as six of the standard 16 address lines. To do this, some
of the upper address lines of internal addresses falling in an active window are overridden. Consequently,
the address viewed externally may not match the internal address. Usage of chip-selects identify the
source of the internal address for debugging and selection of the proper external devices.
All memory expansion windows have a fixed size and two have a fixed address location. The third has
two selectable address locations. When an internal address falls into one of these active windows, it is
translated as shown in
Addresses ADDR9–ADDR0 are not affected by memory expansion and are the same externally as they
are internally. Addresses ADDR21–ADDR16 are generated only by memory expansion and are
individually enabled by software-programmable control bits. If not enabled, they may be used as
general-purpose I/O (input/output). Addresses ADDR15–ADDR10 can be the internal addresses or they
can be modified by the memory expansion module. These are not available as general-purpose I/O in
expanded modes.
Freescale Semiconductor
$0000–$03FF
EWDIR
EWEN = 1
$0000–$03FF
EWDIR
or
EWEN = 0
$0400–$07FF
EWDIR = 0,
EWEN = 1
$0400–$07FF
EWDIR = 1,
EWEN = x
or
EWDIR = x,
EWEN = 0
Address
Internal
(2)
= 1,
A21
1
1
1
1
Table
A20
1
1
1
1
8-1.
Table 8-1. Memory Expansion Values
A19
1
1
1
1
MC68HC812A4 Data Sheet, Rev. 7
A18
1
1
1
1
PEA17 PEA16 PEA15 PEA14 PEA13 PEA12 PEA11 PEA10
PEA17 PEA16 PEA15 PEA14 PEA13 PEA12 PEA11 PEA10
A17
1
1
A16
1
1
A15
A15
A15
A14
A14
A14
(1)
A13
A13
A13
A12
A12
A12
A11
A11
A11
A10
A10
A10
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