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22

the half of the byte in memory is the opcode and other half is the address Well, that's one way of doing it, but there are lots of ways of doing it. Instructions don't have to contain the address. Instructions containing the address or operand is usually known as "immediate" mode, but there are various other addressing modes. You could have those ...


3

No, it cannot be calculated from the schematic symbol alone, but only by reading the data sheet corresponding to the part number in that symbol. You example is a perfect demonstration of why - modern chips used multi-phased addressing, and you have to understand exactly how addressing works before you could know the capacity. Read the data sheet for the ...


3

The situation is far more complex than this. The DRAM has sense amplifiers and bus drivers that provide a strong logic level output signal. There are also several layers of logic between the DRAM output and the 1-bit register. A full answer would be quite broad and lengthy, but you should start by studying computer architecture.


2

Delta cycle delay on addr ... you are writing to the PREVIOUS address so you write 0 to addr UUUU.... ditto reading from the previous address. Either think through the pipeline more carefully, or compute addr before the clock edge (i.e. outside the clocked process in a concurrent assignment), or make addr a variable instead of a signal. The phase delay on ...


2

An approach which has used by the PIC series of microcontrollers since the 1970s is to have a pair of addresses which the PIC refers to as FSR (address 4) and INDF (address 0), but could be given other names. The FSR may be read or written like any other register, but an apparent access to INDF (i.e. an instruction whose address field is all zeroes) will ...


1

Is it the right way to think about memory transfers in computers? no. In no data bus I can think of, a data-storing capacitor would be discharged directly to the bus to drive it - I mean, that would mean that each of the RAM cells would have to store an incredible amount of energy, just to "swing around" the bus. Instead, there's always a readout ...


1

My opinion? Don't instantiate. Infer wherever you possibly can. Find out how your synth tool infers BRAM and write memory that it can translate into BRAM. (It's just an array; you may need to clock the address and/or data to make it synchronous). Semi-dual port ... limitation on read may only apply when concurrently writing to the same address? Link to the ...


1

ram contains 64 memory units, so addr ranges from 0 to 63. A 6-bit wide signal is enough to hold a number from 0 to 63. From ram[addr]<=data; and assign out = ram[addr_reg];, you can see addr represents a binary number. It's not meant to be used as 6 individual signals.


1

Yes it is. The part number has "128M16" in it and it says it is DDR3 memory. From this alone, it can be assumed to have 128M addresses, each address containing 16 bits of data, equalling the said 256 megabytes or 8 gigabits of memory.


1

That’s a DRAM with a multiplexed address bus (row, column) and multiple banks (8 - from the three BAx bits). You’ll need to consult the datasheet based on the part number, which you’ve done, to determine its capacity. This is because there are more row bits than column ones, so without a ‘peek inside’ at the DRAM architecture you don’t really know the total ...


1

Both implementations are possible. The choice of the implementation depends on the optimization of the design software. However you can control the way it is implemented by using directives. First, in the following example in Quartus II the software design has chosen to use memory: library IEEE; use ieee.numeric_std.all; use IEEE.STD_LOGIC_1164.ALL; entity ...


1

TLDR Jump straight down to the "Summary" at the bottom. Details: @duskwuff -inactive- answered the crux of my question in her/his answer here, but I'd like to add some additional insight and also answer my own follow-up questions I wrote in the comments under his answer. First off, the "Basic Linker Script Concepts" section of the GNU ...


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