MCF51EM256CLK Freescale Semiconductor, MCF51EM256CLK Datasheet - Page 230

• Manufacturer Part Number: MCF51EM256CLK
• Description: IC MCU 32BIT 256KB FLASH 80LQFP
• Manufacturer: Freescale Semiconductor
• Series: MCF51EMr

Specifications of MCF51EM256CLK

• Core Processor: Coldfire V1
• Core Size: 32-Bit
• Speed: 50MHz
• Connectivity: I²C, SCI, SPI
• Peripherals: LCD, LVD, PWM, WDT
• Number Of I /o: 56
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Data Converters: A/D 12x16b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-LQFP
• Processor Series: MCF51EM
• Core: ColdFire V1
• Data Bus Width: 32 bit
• Data Ram Size: 16 KB
• Interface Type: RS-232, LIN
• Maximum Clock Frequency: 50 MHz
• Number Of Timers: 3
• Operating Supply Voltage: 1.8 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: JLINK-CF-BDM26, EWCF
• Development Tools By Supplier: DEMOEM
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Multiply-Accumulate Unit (MAC)
} macState;
The following assembly language routine shows the proper sequence for a correct MAC state save. This
code assumes all Dn and An registers are available for use, and the memory location of the state save is
defined by A7.
MAC_state_save:
This code performs the MAC state restore:
MAC_state_restore:
Executing this sequence type can correctly save and restore the exact state of the MAC programming
model.
9.3.1.3
MULS and MULU are unaffected by fractional-mode operation; operands remain assumed to be integers.
9.3.1.4
The scale factor is ignored while the MAC is in fractional mode.
9.3.2
Table 9-6
9-8
Multiply Signed
Multiply Unsigned
Multiply Accumulate
Multiply Accumulate
with Load
Load Accumulator
Store Accumulator
Command
int macsr;
move.l
clr.l
move.l
move.l
move.l
movem.l #0x00e0,(a7)
movem.l (a7),#0x00e0; restore the state from memory
move.l
move.l
move.l
move.l
summarizes MAC unit instructions.
MAC Instruction Set Summary
MULS/MULU
Scale Factor in MAC or MSAC Instructions
MCF51EM256 Series ColdFire Integrated Microcontroller Reference Manual, Rev. 1.11
macsr,d7
d0
d0,macsr
acc,d5
mask,d6
#0,macsr
d5,acc
d6,mask
d7,macsr
muls <ea>y,Dx
mulu <ea>y,Dx
mac Ry,RxSF
msac Ry,RxSF
mac Ry,RxSF,Rw
msac Ry,RxSF,Rw
move.l {Ry,#imm},ACC
move.l ACC,Rx
Mnemonic
Table 9-6. MAC Instruction Summary
; save the macsr
; zero the register to ...
; disable rounding in the macsr
; save the accumulator
; save the address mask
; move the state to memory
; disable rounding in the macsr
; restore the accumulator
; restore the address mask
; restore the macsr
Multiplies two signed operands yielding a signed result
Multiplies two unsigned operands yielding an unsigned result
Multiplies two operands, then adds/subtracts the product
to/from the accumulator
Multiplies two operands, combines the product to the
accumulator while loading a register with the memory
operand
Loads the accumulator with a 32-bit operand
Writes the contents of the accumulator to a CPU register
Description
Freescale Semiconductor