Altera MAX 10 Embedded Memory User Manual

MAX 10 Embedded Memory User Guide

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TOC-2

MAX 10 Embedded Memory Overview.............................................................. 1-1

MAX 10 Embedded Memory Architecture and Features...................................2-1

MAX 10 Embedded Memory General Features...................................................................................... 2-1

Control Signals.................................................................................................................................2-1

Parity Bit............................................................................................................................................2-2

Read Enable.......................................................................................................................................2-2

Read-During-Write......................................................................................................................... 2-3

Byte Enable........................................................................................................................................2-3

Packed Mode Support..................................................................................................................... 2-4

Address Clock Enable Support.......................................................................................................2-5

Asynchronous Clear........................................................................................................................ 2-6

MAX 10 Embedded Memory Operation Modes.....................................................................................2-7

Supported Memory Operation Modes..........................................................................................2-7

MAX 10 Embedded Memory Clock Modes.............................................................................................2-9

Asynchronous Clear in Clock Modes........................................................................................... 2-9

Output Read Data in Simultaneous Read and Write................................................................2-10

Independent Clock Enables in Clock Modes.............................................................................2-10

MAX 10 Embedded Memory Configurations....................................................................................... 2-10

Port Width Configurations.......................................................................................................... 2-10

Mixed-Width Port Configurations..............................................................................................2-11

Maximum Block Depth Configuration.......................................................................................2-12

MAX 10 Embedded Memory Design Consideration..........................................3-1

Implement External Conflict Resolution..................................................................................................3-1

Customize Read-During-Write Behavior.................................................................................................3-1

Same-Port Read-During-Write Mode.......................................................................................... 3-2

Mixed-Port Read-During-Write Mode.........................................................................................3-3

Consider Power-Up State and Memory Initialization............................................................................3-5

Control Clocking to Reduce Power Consumption................................................................................. 3-5

Selecting Read-During-Write Output Choices........................................................................................3-6

RAM: 1-Port IP Core References........................................................................ 4-1

RAM: 1-Port IP Core Signals For MAX 10 Devices................................................................................4-2

RAM: 1-Port IP Core Parameters For MAX 10 Devices........................................................................4-3

RAM: 2-PORT IP Core References.....................................................................5-1

RAM: 2-Ports IP Core Signals (Simple Dual-Port RAM) For MAX 10 Devices................................ 5-5

RAM: 2-Port IP Core Signals (True Dual-Port RAM) for MAX 10 Devices.......................................5-7

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TOC-3

RAM: 2-Port IP Core Parameters for MAX 10 Devices.........................................................................5-9

ROM: 1-PORT IP Core References.....................................................................6-1

ROM: 1-PORT IP Core Signals For MAX 10 Devices............................................................................6-2

ROM: 1-PORT IP Core Parameters for MAX 10 Devices..................................................................... 6-4

ROM: 2-PORT IP Core References.....................................................................7-1

ROM: 2-PORT IP Core Signals for MAX 10 Devices.............................................................................7-3

ROM:2-Port IP Core Parameters For MAX 10 Devices.........................................................................7-5

Shift Register (RAM-based) IP Core References................................................8-1

Shift Register (RAM-based) IP Core Signals for MAX 10 Devices.......................................................8-1

Shift Register (RAM-based) IP Core Parameters for MAX 10 Devices............................................... 8-2

FIFO IP Core References.....................................................................................9-1

FIFO IP Core Signals for MAX 10 Devices..............................................................................................9-2

FIFO IP Core Parameters for MAX 10 Devices.......................................................................................9-4

ALTMEMMULT IP Core References................................................................10-1

ALTMEMMULT IP Core Signals for MAX 10 Devices.......................................................................10-1

ALTMEMMULT IP Core Parameters for MAX 10 Devices............................................................... 10-2

Additional Information for MAX 10 Embedded Memory User Guide............ A-1

Document Revision History for MAX 10 Embedded Memory User Guide.......................................A-1

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MAX 10 Embedded Memory Overview

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MAX® 10 embedded memory block is optimized for applications such as high throughput packet processing, embedded processor program, and embedded data storage.

2015 Altera Corporation. All rights reserved. ALTERA, ARRIA, CYCLONE, ENPIRION, MAX, MEGACORE, NIOS, QUARTUS and STRATIX words and logos are trademarks of Altera Corporation and registered in the U.S. Patent and Trademark Office and in other countries. All other words and logos identified as trademarks or service marks are the property of their respective holders as described at www.altera.com/common/legal.html. Altera warrants performance of its semiconductor products to current specifications in accordance with Altera's standard warranty, but reserves the right to make changes to any products and services at any time without notice. Altera assumes no responsibility or liability arising out of the application or use of any information, product, or service described herein except as expressly agreed to in writing by Altera. Altera customers are advised to obtain the latest version of device specifications before relying on any published information and before placing orders for products or services.

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MAX 10 Embedded Memory Architecture and

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The MAX 10 embedded memory structure consists of 9,216-bit (including parity bits) blocks. You can use each M9K block in different widths and configuration to provide various memory functions such as RAM, ROM, shift registers, and FIFO.

The following list summarizes the MAX 10 embedded memory features:

• Embedded memory general features

• Embedded memory operation modes

• Embedded memory clock modes

Related Information

MAX 10 Device Overview

For information about MAX 10 devices embedded memory capacity and distribution

MAX 10 Embedded Memory General Features

MAX 10 embedded memory supports the following general features:

Features

• 8,192 memory bits per block (9,216 bits per block including parity).

• Independent read-enable (rden) and write-enable (wren) signals for each port.

• Packed mode in which the M9K memory block is split into two 4.5 K single-port RAMs.

• Variable port configurations.

• Single-port and simple dual-port modes support for all port widths.

• True dual-port (one read and one write, two reads, or two writes) operation.

• Byte enables for data input masking during writes.

• Two clock-enable control signals for each port (port A and port B).

• Initialization file to preload memory content in RAM and ROM modes.

Control Signals

The clock-enable control signal controls the clock entering the input and output registers and the entire M9K memory block. This signal disables the clock so that the M9K memory block does not see any clock edges and does not perform any operations.

ISO 9001:2008 Registered

clock_b

clocken_aclock_a

clocken_b

aclr_b

aclr_a

Dedicated Row LAB Clocks

rden_b

rden_a

Local Interconnect

byteena_b

byteena_a

addressstall_b

addressstall_a

wren_a

wren_b

2-2

Parity Bit

The rden and wren control signals control the read and write operations for each port of the M9K memory blocks. You can disable the rden or wren signals independently to save power whenever the operation is not required.

Figure 2-1: Register Clock, Clear, and Control Signals Implementation in M9K Embedded Memory Block

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Parity Bit

You can perform parity checking for error detection with the parity bit along with internal logic resources. The M9K memory blocks support a parity bit for each storage byte. You can use this bit as either a parity bit or as an additional data bit. No parity function is actually performed on this bit. If error detection is not desired, you can use the parity bit as an additional data bit.

Read Enable

M9K memory blocks support the read enable feature for all memory modes.

If you... ...Then

Create the read-enable port and perform a write operation with the read enable port deasserted

The data output port retains the previous values that are held during the most recent active read enable.

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Read-During-Write

If you... ...Then

2-3

• Activate the read enable during a write operation, or

• Do not create a read-enable signal

Read-During-Write

The read-during-write operation occurs when a read operation and a write operation target the same memory location at the same time.

The read-during-write operation operates in the following ways:

• Same-port

• Mixed-port

Related Information

Customize Read-During-Write Behavior on page 3-1

Byte Enable

• Memory block that are implemented as RAMs support byte enables.

• The byte enable controls mask the input data, so that only specific bytes of data are written. The unwritten bytes retain the values written previously.

• The write enable (wren) signal, together with the byte enable (byteena) signal, control the write operations on the RAM blocks. By default, the byteena signal is high (enabled) and only the wren signal controls the writing.

• The byte enable registers do not have a clear port.

• M9K blocks support byte enables when the write port has a data width of ×16, ×18, ×32, or ×36 bits.

• Byte enables operate in a one-hot fashion. The LSB of the byteena signal corresponds to the LSB of the data bus. For example, if byteena = 01 and you are using a RAM block in ×18 mode, data[8:0] is enabled and data[17:9] is disabled. Similarly, if byteena = 11, both data[8:0] and data[17:9] are enabled.

• Byte enables are active high.

The output port shows:

• the new data being written,

• the old data at that address, or

• a “Don't Care” value when read-during-write occurs at the same address location.

Byte Enable Controls

Table 2-1: M9K Blocks Byte Enable Selections

byteena[3:0]

datain x 16 datain x 18 datain x 32 datain x 36

[0] = 1 [7:0] [8:0] [7:0] [8:0] [1] = 1 [15:8] [17:9] [15:8] [17:9] [2] = 1 — — [23:16] [26:18] [3] = 1 — — [31:24] [35:27]

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Affected Bytes. Any Combination of Byte Enables is Possible.

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inclock

wren

address

data

q (asynch)

XXXX

a2 a0

doutn

ABFF

FFCD

ABCD ABFF FFCD

ABCD

byteena

XX 10 01 11

XXXX

ABCD

FFFF

ABFF

FFCD

contents at a0 contents at a1 contents at a2

rden

For this functional waveform, New Data Mode is selected.

2-4

Data Byte Output

RAM Blocks Operations

Data Byte Output

If you... ...Then

Deassert a byte-enable bit during a write cycle The old data in the memory appears in the

corresponding data-byte output.

Assert a byte-enable bit during a write cycle The corresponding data-byte output depends on the

Quartus® II software setting. The setting can be either the newly written data or the old data at that location.

This figure shows how the wren and byteena signals control the RAM operations.

Figure 2-2: Byte Enable Functional Waveform

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Packed Mode Support

You can implement two single-port memory blocks in a single block under the following conditions:

• Each of the two independent block sizes is less than or equal to half of the M9K block size. The

• Each of the single-port memory blocks is configured in single-clock mode.

Related Information

MAX 10 Embedded Memory Clock Modes on page 2-9

maximum data width for each independent block is 18 bits wide.

MAX 10 Embedded Memory Architecture and Features

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address[0]

address[N]

addressstall

clock

address[0]

address[N]

address[0]

inclock

rden

rdaddress

q (synch)

a1 a2 a3 a4 a5

q (asynch)

latched address (inside memory)

dout0

dout1

dout4

dout1

dout4

dout5

addressstall

doutn-1

dout1

doutn

dout1

dout0

dout1

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Address Clock Enable Support

• The address clock enable feature holds the previous address value for as long as the address clock enable signal (addressstall) is enabled (addressstall = 1).

• When you configure M9K memory blocks in dual-port mode, each port has its own independent address clock enable.

• Use the address clock enable feature to improve the effectiveness of cache memory applications during a cache-miss.

• The default value for the addressstall signal is low.

• The address register output feeds back to its input using a multiplexer. The addressstall signal selects the multiplexer output.

Figure 2-3: Address Clock Enable Block Diagram

Address Clock Enable Support

2-5

Address Clock Enable During Read Cycle Waveform

MAX 10 Embedded Memory Architecture and Features

Figure 2-4: Address Clock Enable Waveform During Read Cycle

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inclock

wren

wraddress

a0 a1 a2 a3 a4 a5

an a0

a4 a5

latched address (inside memory)

addressstall

data

01 02

03 04

contents at a0 contents at a1 contents at a2 contents at a3 contents at a4 contents at a5

XX XX

aclr

aclr at latch

clk

a1 a0 a1

2-6

Address Clock Enable During Write Cycle Waveform

Figure 2-5: Address Clock Enable Waveform During Write Cycle

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Asynchronous Clear

You can selectively enable asynchronous clear per logical memory using the RAM: 1-PORT and RAM: 2PORT IP cores.

The M9k block supports asynchronous clear for:

• Read address registers: Asserting asynchronous clear to the read address register during a read operation might corrupt the memory content.

• Output registers: When applied to output registers, the asynchronous clear signal clears the output registers and the effects are immediately seen. If your RAM does not use output registers, you can still clear the RAM outputs using the output latch asynchronous clear feature.

• Output latches

Input registers other than read address registers are not supported.

Note:

Figure 2-6: Output Latch Asynchronous Clear Waveform

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Related Information

• Internal Memory (RAM and ROM) User Guide.

Resetting Registers in M9K Blocks

There are three ways to reset registers in the M9K blocks:

• Power up the device

• Use the aclr signal for output register only

• Assert the device-wide reset signal using the DEV_CLRn option

MAX 10 Embedded Memory Operation Modes

The M9K memory blocks allow you to implement fully-synchronous SRAM memory in multiple operation modes. The M9K memory blocks do not support asynchronous (unregistered) memory inputs.

Note: Violating the setup or hold time on the M9K memory block input registers may corrupt memory

contents. This applies to both read and write operations.

Supported Memory Operation Modes

Resetting Registers in M9K Blocks

2-7

Table 2-2: Supported Memory Operation Modes in the M9K Embedded Memory Blocks

Memory Operation Mode Related IP Core Description

Single-port RAM RAM: 1-PORT IP Core

Single-port mode supports non-simultaneous read and write operations from a single address.

Use the read enable port to control the RAM output ports behavior during a write operation:

• To show either the new data being written or the old data at that address, activate the read enable during a write operation.

• To retain the previous values that are held during the most recent active read enable, perform the write operation with the read enable port deasserted.

Simple dual-port RAM

RAM: 2-PORT IP Core

You can simultaneously perform one read and one write operations to different locations where the write operation happens on port A and the read operation happens on port B.

True dual-port RAM RAM: 2-PORT IP Core

You can perform any combination of two port operations:

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• two reads, two writes, or,

• one read and one write at two different clock frequencies.

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2-8

Supported Memory Operation Modes

Memory Operation Mode Related IP Core Description

Single-port ROM ROM: 1-PORT IP Core Only one address port is available for read

operation. You can use the memory blocks as a ROM.

• Initialize the ROM contents of the memory blocks using a .mif or .hex file.

• The address lines of the ROM are registered.

• The outputs can be registered or unregistered.

• The ROM read operation is identical to the read operation in the single-port RAM configuration.

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Dual-port ROM ROM: 2-PORT IP Core

Shift-register

Shift Register (RAMbased) IP Core

FIFO FIFO IP Core

The dual-port ROM has almost similar functional ports as single-port ROM. The difference is dualport ROM has an additional address port for read operation.

You can use the memory blocks as a ROM.

• Initialize the ROM contents of the memory blocks using a .mif or .hex file.

• The address lines of the ROM are registered.

• The outputs can be registered or unregistered.

• The ROM read operation is identical to the read operation in the single-port RAM configuration.

You can use the memory blocks as a shift-register block to save logic cells and routing resources.

The input data width (w), the length of the taps (m), and the number of taps (n) determine the size of a shift register (w × m × n).

You can cascade memory blocks to implement larger shift registers.

You can use the memory blocks as FIFO buffers.

Memory-based multiplier

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• Use the FIFO IP core in single clock FIFO (SCFIFO) mode and dual clock FIFO (DCFIFO) mode to implement single- and dual-clock FIFO buffers in your design.

• Use dual clock FIFO buffers when transferring data from one clock domain to another clock domain.

• The M9K memory blocks do not support simultaneous read and write from an empty FIFO buffer.

ALTMEMMULT IP Core You can use the memory blocks as a memory-based

multiplier.

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Related Information

MAX 10 Embedded Memory Related IPs

MAX 10 Embedded Memory Clock Modes

Modes

2-9

Clock Mode Description

Independent Clock Mode

A separate clock is available for the following ports:

• Port A—Clock A controls all registers on the port A side.

• Port B—Clock B controls all registers on the port B side.

Input/Output Clock Mode

• M9K memory blocks can implement input or output clock mode for single-port, true dual-port, and simple dual-port memory modes.

• An input clock controls all input registers to the memory block, including data, address,

byteena, wren, and rden registers.

• An output clock controls the data-output registers.

Read or Write Clock Mode

• M9K memory blocks support independent clock enables for both the read and write clocks.

• A read clock controls the data outputs, read address, and read enable registers.

• A write clock controls the data inputs, write address, and write enable registers.

True

Dual-

Port

Simple

Dual-

Port

Single-

Port

ROM FIFO

Yes — — Yes —

Yes Yes Yes Yes —

— Yes — — Yes

Single-Clock Mode

Related Information

A single clock, together with a clock enable, controls all registers of the memory block.

• Packed Mode Support on page 2-4

• Control Clocking to Reduce Power Consumption on page 3-5

• Output Read Data in Simultaneous Read and Write on page 2-10

Asynchronous Clear in Clock Modes

In all clock modes, asynchronous clear is available only for output latches and output registers. For independent clock mode, this is applicable on port A and port B.

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Yes Yes Yes Yes Yes

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Output Read Data in Simultaneous Read and Write

If you perform a simultaneous read/write to the same address location using the read or write clock mode, the output read data is unknown. If you want the output read data to be a known value, use single-clock or input/output clock mode and then select the appropriate read-during-write behavior in the RAM: 1PORT and RAM: 2-PORT IP cores.

Related Information

MAX 10 Embedded Memory Clock Modes on page 2-9

Independent Clock Enables in Clock Modes

Table 2-3: Supported Clock Modes for Independent Clock Enables

Clock Mode Description

Read/write Supported for both the read and write clocks. Independent Supported for the registers of both ports.

MAX 10 Embedded Memory Configurations

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Table 2-4: Maximum Configurations Supported for M9K Embedded Memory Blocks

Feature M9K Block

8192 × 1

4096 × 2

2048 × 4

1024 × 8

Configurations (depth × width)

1024 × 9

512 × 16

512 × 18

256 × 32

256 × 36

Port Width Configurations

The following equation defines the port width configuration: Memory depth (number of words) × Width of the data input bus.

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• If your port width configuration (either the depth or the width) is more than the amount an internal memory block can support, additional memory blocks (of the same type) are used. For example, if you configure your M9K as 512 × 36, which exceeds the supported port width of 512 × 18, two M9Ks are used to implement your RAM.

• In addition to the supported configuration provided, you can set the memory depth to a non-power of two, but the actual memory depth allocated can vary. The variation depends on the type of resource implemented.

• If the memory is implemented in dedicated memory blocks, setting a non-power of two for the memory depth reflects the actual memory depth.

• When you implement your memory using dedicated memory blocks, refer to the Fitter report to check the actual memory depth.

Mixed-Width Port Configurations

The mixed-width port configuration support allows you to read and write different data widths to an M9K memory block. The following memory modes support the mixed-width port configuration:

• Simple dual-port RAM

• True dual-port RAM

• FIFO

Mixed-Width Port Configurations

2-11

M9K Block Mixed-Width Configurations (Simple Dual-Port RAM)

Read Port

8192 × 1 4096 × 2 2048 × 4 1024 × 8 512 × 16 256 × 32 1024 × 9 512 × 18 256 × 36

8192 × 1 Yes Yes Yes Yes Yes Yes — — — 4096 × 2 Yes Yes Yes Yes Yes Yes — — — 2048 × 4 Yes Yes Yes Yes Yes Yes — — — 1024 × 8 Yes Yes Yes Yes Yes Yes — — — 512 × 16 Yes Yes Yes Yes Yes Yes — — — 256 × 32 Yes Yes Yes Yes Yes Yes — — — 1024 × 9 — — — — — — Yes Yes Yes 512 × 18 — — — — — — Yes Yes Yes 256 × 36 — — — — — — Yes Yes Yes

Write Port

M9K Block Mixed-Width Configurations (True Dual-Port RAM Mode)

Read Port

8192 × 1 4096 × 2 2048 × 4 1024 × 8 512 × 16 1024 × 9 512 × 18

Write Port

8192 × 1 Yes Yes Yes Yes Yes — — 4096 × 2 Yes Yes Yes Yes Yes — — 2048 × 4 Yes Yes Yes Yes Yes — — 1024 × 8 Yes Yes Yes Yes Yes — —

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2-12

Maximum Block Depth Configuration

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Read Port

8192 × 1 4096 × 2 2048 × 4 1024 × 8 512 × 16 1024 × 9 512 × 18

Write Port

512 × 16 Yes Yes Yes Yes Yes — — 1024 × 9 — — — — — Yes Yes 512 × 18 — — — — — Yes Yes

Maximum Block Depth Configuration

The Set the maximum block depth parameter allows you to set the maximum block depth of the dedicated memory block you use. You can slice the memory block to your desired maximum block depth. For example, the capacity of an M9K block is 9,216 bits, and the default memory depth is 8K, in which each address is capable of storing 1 bit (8K × 1). If you set the maximum block depth to 512, the M9K block is sliced to a depth of 512 and each address is capable of storing up to 18 bits (512 × 18).

Use this parameter to save power usage in your devices and to reduce the total number of memory blocks used. However, this parameter might increase the number of LEs and affects the design performance.

When the RAM is sliced shallower, the dynamic power usage decreases. However, for a RAM block with a depth of 256, the power used by the extra LEs starts to outweigh the power gain achieved by shallower slices.

The maximum block depth must be in a power of two, and the valid values vary among different dedicated memory blocks.

This table lists the valid range of maximum block depth for M9K memory blocks.

Table 2-5: Valid Range of Maximum Block Depth for M9K Memory Blocks

Memory Block Valid Range

M9K 256 - 8K. The maximum block depth must be in a power of two.

The IP parameter editor prompts an error message if you enter an invalid value for the maximum block depth. Altera recommends that you set the value of the Set the maximum block depth parameter to Auto if you are unsure of the appropriate maximum block depth to set or the setting is not important for your design. The Auto setting enables the Compiler to select the maximum block depth with the appropriate port width configuration for the type of internal memory block of your memory.

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MAX 10 Embedded Memory Design

Port A data in

Port B data in

Port A data out

Port B data out

Mixed-port data flow

Same-port data flow

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There are several considerations that require your attention to ensure the success of your designs.

Implement External Conflict Resolution

In the true dual-port RAM mode, you can perform two write operations to the same memory location. However, the memory blocks do not have internal conflict resolution circuitry.

To avoid unknown data being written to the address, implement external conflict resolution logic to the memory block.

Customize Read-During-Write Behavior

Customize the read-during-write behavior of the memory blocks to suit your design requirements.

Figure 3-1: Difference Between the Two Types of Read-during-Write Operations —Same Port and Mixed Port.

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Related Information

Read-During-Write on page 2-3

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clk_a

wren_a

address_a

data_a

rden_a

q_a (asynch)

a0 a1

A B C D E F

A B C D E

3-2

Same-Port Read-During-Write Mode

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Same-Port Read-During-Write Mode

The same-port read-during-write mode applies to a single-port RAM or the same port of a true dual-port RAM.

Table 3-1: Output Modes for Embedded Memory Blocks in Same-Port Read-During-Write Mode

This table lists the available output modes if you select the embedded memory blocks in the same-port readduring-write mode.

Output Mode Description

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"new data" (flow-through)

"don't care" The RAM outputs reflect the old data at that address before the write

Figure 3-2: Same-Port Read-During-Write: New Data Mode

The new data is available on the rising edge of the same clock cycle on which the new data is written.

When using New Data mode together with byte enable, you can control the output of the RAM.

When byte enable is high, the data written into the memory passes to the output (flow-through).

When byte enable is low, the masked-off data is not written into the memory and the old data in the memory appears on the outputs. Therefore, the output can be a combination of new and old data determined by byteena.

operation proceeds.

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clk_a

wren_a

address_a

data_a

rden_a

a0 a1

A B C D E F

a0(old data) a1(old data)A B D E

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Figure 3-3: Same Port Read-During-Write: Old Data Mode

Mixed-Port Read-During-Write Mode

3-3

Mixed-Port Read-During-Write Mode

The mixed-port read-during-write mode applies to simple and true dual-port RAM modes where two ports perform read and write operations on the same memory address using the same clock—one port reading from the address, and the other port writing to it.

Table 3-2: Output Modes for RAM in Mixed-Port Read-During-Write Mode

Output Mode Description

"old data"

"don't care"

A read-during-write operation to different ports causes the RAM output to reflect the “old data” value at the particular address.

The RAM outputs “don’t care” or “unknown” value.

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a b

a (old data)

b (old data)

clk_a&b

wren_a

address_a

q_b (asynch)

rden_b

a b

address_b

data_a

A B C D E F

D E

In Don't Care mode, the old data is replaced with “Don't Care”.

3-4

Mixed-Port Read-During-Write Operation with Dual Clocks

Figure 3-4: Mixed-Port Read-During-Write: Old Data Mode

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Mixed-Port Read-During-Write Operation with Dual Clocks

For mixed-port read-during-write operation with dual clocks, the relationship between the clocks determines the output behavior of the memory.

If You... ...Then

Use the same clock for the two clocks The output is the old data from the address

location.

Use different clocks The output is unknown during the mixed-port

read-during-write operation. This unknown value may be the old or new data at the address location, depending on whether the read happens before or after the write.

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Consider Power-Up State and Memory Initialization

Consider the power-up state of the different types of memory blocks if you are designing logic that evaluates the initial power-up values, as listed in the following table:

Table 3-3: Initial Power-Up Values of Embedded Memory Blocks

Memory Type Output Registers Power Up Value

3-5

M9K

Used Zero (cleared)

Bypassed Zero (cleared)

By default, the Quartus II software initializes the RAM cells to zero unless you specify a .mif. All memory blocks support initialization with a .mif. You can create .mif files in the Quartus II software

and specify their use with the RAM IP when you instantiate a memory in your design. Even if a memory is preinitialized (for example, using a .mif), it still powers up with its output cleared. Only the subsequent read after power up outputs the preinitialized values.

Only the following MAX 10 configuration modes support memory initialization:

• Single Compressed Image with Memory Initialization

• Single Uncompressed Image with Memory Initialization

Related Information

Selecting Internal Configuration modes.

Provides more information about selecting MAX 10 internal configuration modes.

Control Clocking to Reduce Power Consumption

Reduce AC power consumption in your design by controlling the clocking of each memory block:

• Use the read-enable signal to ensure that read operations occur only when necessary. If your design does not require read-during-write, you can reduce your power consumption by deasserting the readenable signal during write operations, or during the period when no memory operations occur.

• Use the Quartus II software to automatically place any unused memory blocks in low-power mode to reduce static power.

• Create independent clock enable for different input and output registers to control the shut down of a particular register for power saving purposes. From the parameter editor, click More Options (beside the clock enable option) to set the available independent clock enable that you prefer.

Related Information

MAX 10 Embedded Memory Clock Modes on page 2-9

MAX 10 Embedded Memory Design Consideration

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Selecting Read-During-Write Output Choices

• Single-port RAM only supports same-port read-during-write, and the clock mode must be either single clock mode, or input/output clock mode.

• Simple dual-port RAM only supports mixed-port read-during-write, and the clock mode must be either single clock mode, or input/output clock mode.

• True dual-port RAM supports same port read-during-write and mixed-port read-during-write.

• For same port read-during-write, the clock mode must be either single clock mode, input/output

clock mode, or independent clock mode.

• For mixed port read-during-write, the clock mode must be either single clock mode, or input/

output clock mode.

Note:

If you are not concerned about the output when read-during-write occurs and would like to improve performance, select Don't Care. Selecting Don't Care increases the flexibility in the type of memory block being used, provided you do not assign block type when you instantiate the memory block.

Table 3-4: Output Choices for the Same-Port and Mixed-Port Read-During-Write

UG-M10MEMORY

2015.05.04

Memory Block

M9K

Single-Port RAM Simple Dual-

Port RAM

Same-Port

Read-During-

Write

Don’t Care New Data

Mixed-Port

Read-During-

Write

Old Data Don’t Care

Old Data

Same-Port

Read-During-

Write

New Data Old Data

True Dual-Port RAM

Mixed-Port Read-During-Write

Old Data Don’t Care

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MAX 10 Embedded Memory Design Consideration

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Altera MAX 10 Embedded Memory User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

MAX 10 Embedded Memory User Guide

Contents

MAX 10 Embedded Memory Overview

MAX 10 Embedded Memory General Features

Control Signals

Parity Bit

Read Enable

Read-During-Write

Byte Enable

Byte Enable Controls

Data Byte Output

RAM Blocks Operations

Packed Mode Support

Address Clock Enable Support

Address Clock Enable During Read Cycle Waveform

Address Clock Enable During Write Cycle Waveform

Asynchronous Clear

Resetting Registers in M9K Blocks

MAX 10 Embedded Memory Operation Modes

Supported Memory Operation Modes

MAX 10 Embedded Memory Clock Modes

Asynchronous Clear in Clock Modes

Output Read Data in Simultaneous Read and Write

Independent Clock Enables in Clock Modes

MAX 10 Embedded Memory Configurations

Port Width Configurations

Mixed-Width Port Configurations

M9K Block Mixed-Width Configurations (Simple Dual-Port RAM)

M9K Block Mixed-Width Configurations (True Dual-Port RAM Mode)

Maximum Block Depth Configuration

Implement External Conflict Resolution

Customize Read-During-Write Behavior

Same-Port Read-During-Write Mode

Mixed-Port Read-During-Write Mode

Mixed-Port Read-During-Write Operation with Dual Clocks

Consider Power-Up State and Memory Initialization

Control Clocking to Reduce Power Consumption

Selecting Read-During-Write Output Choices