3 ms·
NXP LPC is a big one. Most of the families have an external memory controller (EMC) block that can drive an external DRAM at a small multiple of the system cloc
by joezydeco 5y ago
NXP LPC is a big one. Most of the families have an external memory controller (EMC) block that can drive an external DRAM at a small multiple of the system clock frequency. The EMC init happens in the secondary boot, usually loaded from the small on-board flash or an offboard EEPROM.
I regularly use the 1788 + a meg or two of DRAM to hold an LCD framebuffer. The LPC has a really nice interconnect between EMC and the internal LCD controller block and will drive the display all on its own (with a hardware cursor) once it is initialized.
- blueflow 5y agoDuckduckgo, "NXP LPC", sidebar, quote from wikipedia: > LPC is a family of 32-bit microcontroller integrated circuits by NXP Semiconductors. Not a microprocessor. You are the second guy to pull this on me. Do people even read what i write? Did i write unclearly?
- joezydeco 5y agoPerhaps you're just outdated. Nobody ships a core alone on a chip anymore. That died with the 68000 or ARM7TDMI.
- blueflow 5y agox86 is a classic microprocessor architecture. I'm confident it is not outdated yet, as im using a fairly modern x86 desktop right now at the moment. RAM and chipset are separate from the processor.
- joezydeco 5y agoThen maybe the hackers using x86 boards in their 'embedded Linux systems' can chime in.
- blueflow 5y agoPerfect, as i own a RDC 3210 board. Here is someone else with the same board + pictures: https://forum.archive.openwrt.org/viewtopic.php?id=19168 https://forum.archive.openwrt.org/viewtopic.php?id=19168 It has a x86 Microprocessor architecture, but it is not IBM PC compatible because it does not has an BIOS, instead using a more embedded-style RedBoot setup. Maybe you should do a quick web search before talking shit.
- detaro 5y ago> x86 desktop right now at the moment. RAM and chipset "chipset" is very different than a traditional microprocessor chipset though on that. E.g. you don't have an exposed system bus outside the CPU, but rather specialized interfaces. (And ARM systems have evolved the same way over their history)
- blueflow 5y agoWhat about the slots i plug my RAM sticks into? Do they not count because it goes over the north bridge?
- detaro 5y agoModern x86 CPUs integrate the DRAM controller directly (e.g. with Intel ever since Nehalem, ~2008) and not over a bus through the northbridge. From that point on I wouldn't count it if you insist on a strict definition, no - it's roughly the same as if you put a socket between a current higher-end ARM chip with external memory and the connected DRAM chips. Chipset is relegated to dealing with I/O to peripherals mostly - and nowadays the CPUs also provide PCIe lanes directly, with the chipset often adding a few more, often slower ones. Traditional microprocessors are getting really rare, even though pretty much all the modern architectures started as them, and thus some use the term more widely. Some vendors use the differentiation between microcontrollers and application processors now, which also isn't a 100% clear line and explicit crossover models existing, but more useful today and avoids the fights over "what's a microprocessor today". (where "application processor" ~ "can reasonably run a full OS like Linux"). But that's also often limited to discussion in embedded use cases again, e.g. I don't know if they'd call a standard desktop CPU that or insist on some arbitrary level of "embeddedness"... Not that standard desktop CPUs don't end up embedded, but that's another discussion entirely.
- blueflow 5y agoThis is a useful explanation. For the article, i don't want to leave it standing as it is. Redefining "Microprocessors" as "having an MMU" is making communication about these topics very unpleasant, especially when its about Retrocomputing. Same pains as i ranted about in https://news.ycombinator.com/item?id=30278936 https://news.ycombinator.com/item?id=30278936 .