Upgrade the playstation 1 cpu or even recreate entire console motherboard

[]-[itman]

I was under the impression that the earlier PlayStation were like the earlier Amiga, if you change the hardware some games might not work properly after because they were written specifically for that hardware? What would be the benefit of the modifications you want to do, simply faster/stabler or do you want to run games/programs from other versions, maybe a different OS?

All games on the PS1 were written specifically for its hardware.

From my own searchers just quickly though, Its saying the GTE as part of the GPU not the CPU

Where are you seeing that? Every source I have found says it is in the CPU.

PlayStation technical specifications - Wikipedia

en.wikipedia.org

PlayStation Architecture | A Practical Analysis

An in-depth analysis that explains how this console works internally

www.copetti.org

 

[winetime]

All games on the PS1 were written specifically for its hardware.



Where are you seeing that? Every source I have found says it is in the CPU.

PlayStation technical specifications - Wikipedia

en.wikipedia.org

View attachment 365604

PlayStation Architecture | A Practical Analysis

An in-depth analysis that explains how this console works internally

www.copetti.org

View attachment 365606

Sony GTE GPU Specs

2 Pixel Shaders, 1 Vertex Shaders, 3 TMUs, 1 ROPs

www.techpowerup.com

On this site its saying its part of the gpu

Post magically merged: Mar 27, 2024

Super secret squirll stuff. I still think its gonna be a revision of the cpu. So not every revision has an all the co processors in it is what i think cause there is bunch of revisions to the cpu

GitHub - emu-russia/psxcpu: Reverse engineering of the SONY PlayStation CPU.

Reverse engineering of the SONY PlayStation CPU. Contribute to emu-russia/psxcpu development by creating an account on GitHub.

github.com

There were 10 revisions of the cpu

 

[]-[itman]

Sony GTE GPU Specs

2 Pixel Shaders, 1 Vertex Shaders, 3 TMUs, 1 ROPs

www.techpowerup.com

On this site its saying its part of the gpu

Post magically merged: Mar 27, 2024

Super secret squirll stuff. I still think its gonna be a revision of the cpu. So not every revision has an all the co processors in it is what i think cause there is bunch of revisions to the cpu

GitHub - emu-russia/psxcpu: Reverse engineering of the SONY PlayStation CPU.

Reverse engineering of the SONY PlayStation CPU. Contribute to emu-russia/psxcpu development by creating an account on GitHub.

github.com

There were 10 revisions of the cpu

They (Toms) are wrong. They show the GPU and GPU specs and think its name is GTE, but it's not. The GTE is completely separate and is part of the CPU and doesn't have any of the specs they list.

Every CPU has the co-processors in it. The system wouldn't function without them. Revisions are done for bug fixing, cost improvements, or efficiency improvements (allowing for more slender consoles). The chip functionality has to stay the same though, or it won't work.

 

[rainless]

Yes, for patents, it's 20 years. Copyrights, though, are much longer and apply to the software side.

Ahh... That's probably RED's angle with CinemaDNG then... a copyright and not a trademark. (Though in my opinion that copyright should rightfully belong to Adobe... since they created DNG and CinemaDNG is just a derivative work of that.)

I have a friend who can do all the solder rework no problem. They have all the equipment needed. They have a local shop near me. TechGenius i believe the company name still is. Its in Montclair CA. They do bga rework, mostly repairing cell phones,ps2,ps3,ps4,xbox,ps5,pcs,gpus etc: you name it, they do it. He is the best that i know of, people from all around send him things that they can't fix and he fixes them.

He once hand reballed the new atari upgradeing the cpu in it for me. I almost got a 8 core Atari... Thats a tale for another time. It didn't work because i chose the wrong chip. I later found out that there is a apu that would work. The new atari is a windows pc so there a bunch of choices for apu. It uses a standard bga cpu socket. I posted on atari forum about that failed project. I didn't want to throw anymore money at the project but it was fun to try to upgrade the Atari. It only cost me about 600$ to give that a shot.

Post magically merged: Mar 26, 2024

So i want to say hey if you want a fun project upgrade the atari vcs to an 8 core apu

Post magically merged: Mar 26, 2024

I also upgraded the internal bga storage chip on the atari vcs to double the size but once you do that it creates problems. Such as no being able to run the atari os anymore. So the system basically just functions as a computer. Again there is a bga storage chip on the motherboard that the atari os is on, I had that desoldered and soldered in a larger one and it worked so that is definitely possible.

Getting back to the subject at hand: What's the point of an upgraded Atari or an Upgraded Playstation 1? I'm pretty sure my DISHWASHER is powerful enough to run Atari games... and it has wifi. So what good is a more powerful CPU going to do you?

Same with PS1 games... Why?

I mean... if you run an emulator... you can do things like upscale the graphics and double the frame rate and run mods and all that. But running just the native Playstation OS with a more powerful processor... it isn't going to do a thing for you. Especially not if you're going to run the original disks from like 30 years ago or however long it's been.

I dunno... Maybe someone already answered this earlier.

There are all sorts of portable systems out now that will let you run ANY systems games... with varying degrees of processing power. That seems to be where everything is going now. Now that COVID's over... people want to leave the house.

 

[winetime]

How can we be certain that all 10 revisions of the cpu have all the co-processors? According to cpu world, R3000 has at least 1 CP. Could it be possible that these components were separate at first then merge to save space. As you said slim the console down through revision. I just find it a little difficult to believe that sony created cpu only a few years later after the invention of GTE by SGI. Were talking 1981 to 1994. In 1981 it was a separate chip that sgi created. You may be right though so the GTE is still gonna be the deciding factor on whether or not the system will work. Unless by some small chance the philips velo processor has similiar co-processors that would function enough to still boot the system. After all it is a handheld pc.

I have some hope but not much. Makes me wonder witch revision of playstation 1 to attempt this on.

Post magically merged: Mar 27, 2024

Ahh... That's probably RED's angle with CinemaDNG then... a copyright and not a trademark. (Though in my opinion that copyright should rightfully belong to Adobe... since they created DNG and CinemaDNG is just a derivative work of that.)



Getting back to the subject at hand: What's the point of an upgraded Atari or an Upgraded Playstation 1? I'm pretty sure my DISHWASHER is powerful enough to run Atari games... and it has wifi. So what good is a more powerful CPU going to do you?

Same with PS1 games... Why?

I mean... if you run an emulator... you can do things like upscale the graphics and double the frame rate and run mods and all that. But running just the native Playstation OS with a more powerful processor... it isn't going to do a thing for you. Especially not if you're going to run the original disks from like 30 years ago or however long it's been.

I dunno... Maybe someone already answered this earlier.

There are all sorts of portable systems out now that will let you run ANY systems games... with varying degrees of processing power. That seems to be where everything is going now. Now that COVID's over... people want to leave the house.

The Atari would be able to run much more high end games in steam. The Atari VCS is a windows pc and an atari emulator. It will boot right in windows. It only has a dual core processor with 4 threads i believe if i remember correctly. But you would be able to make it have 8 cores. I do not remember all the specs of the VCS I would have to research and get back to you. So you would have a 8 core steam machine and an atari emulator in opinion it would just be an awsome all around gaming pc. I had a friend who could also use this as a service to sell to people. Atari vcs upgrade service witch will happen in the future i think.

Its a childhood thing. I have always wanted to improve the ps1 being a modder. Or at least i was a modder. I used to mod and sell playstations

 

[]-[itman]

How can we be certain that all 10 revisions of the cpu have all the co-processors? According to cpu world, R3000 has at least 1 CP. Could it be possible that these components were separate at first then merge to save space. As you said slim the console down through revision. I just find it a little difficult to believe that sony created cpu only a few years later after the invention of GTE by SGI. Were talking 1981 to 1994. In 1981 it was a separate chip that sgi created.

13 years is a long time, not sure why you think they couldn't incorporate the SGI tech 13 years after they created it, 13 years in technology is an eternity. They also didn't just buy the chip from SGI, they licensed the tech (modified it for their needs most likely) and included it as a co-processor inside the CPU. The R3000 series from what I've seen was somewhat modular. Meaning, you got the MIPS core but then there were hooks for up to 4 co-processors that you could also include on the chip. Rather than use the MIPS co-processors, Sony designed their own custom ones for the PS1. This was clearly the design from the beginning. I even found a presentation given by the creator of the PS1 where he shows the original PS1 CPU die with the different modules labeled. You can see the MIPS core as well as the GTE, DMAC, and video decoder. I highly doubt the MIPS CPU you'll get off that PDA will have the required modules (or even compatible pinout but who knows) to work in the PS1 but I do hope you have fun trying!

 

[winetime]

13 years is a long time, not sure why you think they couldn't incorporate the SGI tech 13 years after they created it, 13 years in technology is an eternity. They also didn't just buy the chip from SGI, they licensed the tech (modified it for their needs most likely) and included it as a co-processor inside the CPU. The R3000 series from what I've seen was somewhat modular. Meaning, you got the MIPS core but then there were hooks for up to 4 co-processors that you could also include on the chip. Rather than use the MIPS co-processors, Sony designed their own custom ones for the PS1. This was clearly the design from the beginning. I even found a presentation given by the creator of the PS1 where he shows the original PS1 CPU die with the different modules labeled. You can see the MIPS core as well as the GTE, DMAC, and video decoder. I highly doubt the MIPS CPU you'll get off that PDA will have the required modules (or even compatible pinout but who knows) to work in the PS1 but I do hope you have fun trying!

View attachment 365608

13 years is awhile i guess. I will enjoy giving this a shot. I still got the find the specs of PDA. Again when you google the processor in it you get nothing and even cpu world doesn't have any info on it.

I am also looking into SGI systems

Sony playstation 1 GTE reverse engineered

GitHub - ogamespec/pops-gte: PlayStation GTE Reversing

PlayStation GTE Reversing. Contribute to ogamespec/pops-gte development by creating an account on GitHub.

github.com

I have done some reading and discovered that the GTE may not be needed for basic functions. Meaning the system might boot without it. I read about a similiar system using a core similiar to the gte but it only activates when cpu is overwhelmed. It was also an optional component and the system would function normally without it. 80386 and 80387. Still can't find much on the philips velo 500 specs. Can't find much in the way of the cpu specs it is still a mystery. I might have to go search a library for old books see if anything is published about it. The PDA is coming from CASABLANCA, Morocco so its going to be awhile before i get it. SGI makes a system board with a dual r3000 cpu 40mhz , I am looking for that as well as

 

[winetime]

Hey moderators who have been most helpful to me on here would it be alright for me to repost my gofund me in a separate post or new post

 

[EarthDog]

Hey moderators who have been most helpful to me on here would it be alright for me to repost my gofund me in a separate post or new post

That's not not allowed here, sorry.

Why you posted it, then asked... double posting AGAIN.... I have no idea. You really need to get your **** together before posting. Tired of dealing with it..

 

[winetime]

That's not not allowed here, sorry.

Why you posted it, then asked... double posting AGAIN.... I have no idea. You really need to get your **** together before posting. Tired of dealing with it..

Sorry i didn't know that. It won't happen again, is there a way to take down my earlier post. Hey the double posting isn't happening on purpose i posted the first one yesterday then i posted again this morning. I am still new to this forum. The post should be a completely separate post , Sorry i don't mean to make your job difficult

13 years is a long time, not sure why you think they couldn't incorporate the SGI tech 13 years after they created it, 13 years in technology is an eternity. They also didn't just buy the chip from SGI, they licensed the tech (modified it for their needs most likely) and included it as a co-processor inside the CPU. The R3000 series from what I've seen was somewhat modular. Meaning, you got the MIPS core but then there were hooks for up to 4 co-processors that you could also include on the chip. Rather than use the MIPS co-processors, Sony designed their own custom ones for the PS1. This was clearly the design from the beginning. I even found a presentation given by the creator of the PS1 where he shows the original PS1 CPU die with the different modules labeled. You can see the MIPS core as well as the GTE, DMAC, and video decoder. I highly doubt the MIPS CPU you'll get off that PDA will have the required modules (or even compatible pinout but who knows) to work in the PS1 but I do hope you have fun trying!

View attachment 365608

I found some specs on the PR13700 family mips chips. No mention of a GTE core. But it does support DMA so there should be no issue with DMA. But i also found a website that list a few more possible options for upgrades. Its a list of old devices containing R3000 and R4000 based CPUs.
If the PR13700 in the Philips Velo 500 lacks whats needed to run the ps1 then maybe one of these other devices might have one configured to do so. There a bunch of old devices containing R3000 variants. Maybe one will have a GTE core. Or maybe i just need find away to run an external gte core along side the faster processor or something along those lines. Maybe i could create a separate GTE chip or find one which would be much easier. The GTE has been reverse engineered as well. So i picture in my mind a mod chip containing a GTE running along side the faster processor. Hoping there would be away around the GTE. Possibly upgrade the GPU as well to one that does not require gte but then it complicates everything further but there has to be a way.

Warner's Mips based PDA info Center

Poseidon
From LinuxMIPS

PR31100

PR31100 is is a single-chip, low-cost, integrated embedded processor. PR31100 consists of a 40MHz R3000 3.3V static CMOS CPU with 4 K Instruction / 1 K Data cache memory, w/o MMU, multiple DMA channels and a high-performance and flexible Bus Interface Unit (BIU) and external I/O modules.

This is another option for an upgrade for the ps1 the PR31100


PR31500

Poseidon v1.0

PR31500 is a 37MHz R3000 3.3V static CMOS CPU with R3000A TLB and 4K Instrution / 1K Data cache. PR31500 also contains multi-channel DMA controller, ROM, Flash, RAM, DRAM, SDRAM, SRAM, and PCMCIA controller and Dual-UART, SPI and High-speed serial interface controllers. Philips licensed a version of Toshiba's R3900 MIPS RISC processor core for the PR31500.

TwoChipPIC (for Personal Intelligent Communicator) chipset consists of the PR31500 microcontroller and the UCB1100 analog interface chip. The UCB1100 (http://www.semiconductors.philips.com/pip/UCB1100_2.html) provides a 12-bit audio codec and a 14-bit modem codec, a touchscreen interface, and a 10-bit A/D converter for measuring battery voltages and other analog inputs.

PR31700

Poseidon v1.5

The PR31700 is a 75MHz R3000 (PR3901 Processor Core) with MMU, 4K Instruction / 1K Data cache. PR31700 also contains multi-channel DMA controller, ROM, Flash, RAM, DRAM, SDRAM, SRAM, and PCMCIA controller. It is also identical to the Toshiba 3912 processor from the TX39XX family. It is pretty clear that Philips licensed or bought this core directly from Toshiba.

The TwoChipPIC Plus chipset consists of Philips’ PR31700 and UCB1200 analog chip.

 

[]-[itman]

I found some specs on the PR13700 family mips chips. No mention of a GTE core. But it does support DMA so there should be no issue with DMA.

It is extremely likely that there will still be issues with the DMA. Like I said, having a DMA controller is not unique to the PS1, that doesn't mean it's compatible with another chip's DMA controller. Why? Because the DMA controller in the PS1 was designed to control memory access for the CPU, GPU, and audio chip that are specific to the PS1. It is extremely unlikely that another DMA controller inside of a similar MIPS processor will have enough channels or the proper signalling to support such a configuration.

The GTE has been reverse engineered as well.

It has not.

So i picture in my mind a mod chip containing a GTE running along side the faster processor.

Even if you could get a separate GTE chip, the PS1 is designed for it to be in the CPU. So, you'd need to redesign the motherboard for a place for the GTE, have the proper traces go there, and redesign the CPU to communicate with the GTE externally, all the while making sure the signals and timings are correct for it to all function together. In other words, you're back to square one of a custom design, so you might as well keep it all on one chip.

Hoping there would be away around the GTE. Possibly upgrade the GPU as well to one that does not require gte but then it complicates everything further but there has to be a way.

Same issue as above. It's not just the functionality of the GTE that is needed, it's how it communicates with the rest of the system and the proper timings of the signals. Of course there is a way to do what you want, it's just going to be very expensive to pay someone who has the expertise needed to get it done, like myself and others have said multiple times now.

 

[winetime]

It is extremely likely that there will still be issues with the DMA. Like I said, having a DMA controller is not unique to the PS1, that doesn't mean it's compatible with another chip's DMA controller. Why? Because the DMA controller in the PS1 was designed to control memory access for the CPU, GPU, and audio chip that are specific to the PS1. It is extremely unlikely that another DMA controller inside of a similar MIPS processor will have enough channels or the proper signalling to support such a configuration.



It has not.



Even if you could get a separate GTE chip, the PS1 is designed for it to be in the CPU. So, you'd need to redesign the motherboard for a place for the GTE, have the proper traces go there, and redesign the CPU to communicate with the GTE externally, all the while making sure the signals and timings are correct for it to all function together. In other words, you're back to square one of a custom design, so you might as well keep it all on one chip.



Same issue as above. It's not just the functionality of the GTE that is needed, it's how it communicates with the rest of the system and the proper timings of the signals. Of course there is a way to do what you want, it's just going to be very expensive to pay someone who has the expertise needed to get it done, like myself and others have said multiple times now.

GTE Reverse Engineered or at least its an attempt to better understand the GTE
Githubhttps://github.com/ogamespec/pops-gte
I am not disagreeing with you completely but i am enjoying our conversations they seem to lead to greater insight, at least for me. I thank you for all of your knowledge and experience that you have been sharing. I hope that this thread will lead to solution un-thought off yet. Hopeing for great knowledge and wisdom to suddenly appear from someone who has already tried this. Or even already has had success. Again when you google upgrade ps1 cpu google spits back at you that it can't be done or in other words its impossible. I hope to change that somehow.

 

[]-[itman]

GTE Reverse Engineered or at least its an attempt to better understand the GTE
Githubhttps://github.com/ogamespec/pops-gte
I am not disagreeing with you completely but i am enjoying our conversations they seem to lead to greater insight, at least for me. I thank you for all of your knowledge and experience that you have been sharing. I hope that this thread will lead to solution un-thought off yet. Hopeing for great knowledge and wisdom to suddenly appear from someone who has already tried this. Or even already has had success. Again when you google upgrade ps1 cpu google spits back at you that it can't be done or in other words its impossible. I hope to change that somehow.

If you look at the project details, it was created 13 years ago with no real updates for the last 9 years. Looks like they were able to identify all of the standard cells used (unverified but still impressive) but made little to no progress in actually recreating the design. Seems they completely abandoned the project about 4 years ago (last minor update I could find).

This stuff is hard and very time consuming. It requires the right tools and expertise, something very few people have. Your best shot would be to hope someone who actually could do it, will see it as a passion project and will spend their free time doing it for little to no money. I doubt this person exists, but even if they do, because it is a side project, expect it to take several years at best for them to complete it. That's basically best case scenario but also extremely unlikely. Most likely said person would run out of patience/time and just be satisfied with whatever progress they made before abandoning the project. Other than that, you're going to have to pay someone a lot of money to get them to actually spend their time to get it done, because if you don't, they're going to spend their time making a lot of money on another project.

 

[winetime]

If you look at the project details, it was created 13 years ago with no real updates for the last 9 years. Looks like they were able to identify all of the standard cells used (unverified but still impressive) but made little to no progress in actually recreating the design. Seems they completely abandoned the project about 4 years ago (last minor update I could find).

This stuff is hard and very time consuming. It requires the right tools and expertise, something very few people have. Your best shot would be to hope someone who actually could do it, will see it as a passion project and will spend their free time doing it for little to no money. I doubt this person exists, but even if they do, because it is a side project, expect it to take several years at best for them to complete it. That's basically best case scenario but also extremely unlikely. Most likely said person would run out of patience/time and just be satisfied with whatever progress they made before abandoning the project. Other than that, you're going to have to pay someone a lot of money to get them to actually spend their time to get it done, because if you don't, they're going to spend their time making a lot of money on another project.

found some data sheets on PR31700 family processors using this site
https://www.datasheetcatalog.com/datasheets_pdf/P/R/3/1/PR31500ABC.shtml
I am going to check out all the processors listed here

Warner's Mips based PDA info Center

In the datasheets it doesn't mention customization of co-processors, It hardly mentions the co-processors at all. It shows all the pinouts and timings though. Which i suspect are more important then anything else. Still think the GTE only activates when the processor is overwhelmed by data. Witch may allow for some function without it. If i could get partial function that would be something to work with.

Your right i really do need a passion project worker unless i raise the money to pay someone to do the work. I tried to contact the person who worked on that project reverse engineering gte, i think they are the same person who reverse engineered the cpu. Wondering if they would be interested in working on something like this.

Also looking into SGI systems witch are very expensive and hard to find. Again, they have a board of some kind with dual R3000 clocked at 40mhz. SGI made the GTE basically, Wondering if there system would have a GTE core R3000.

When you google GTE all you get is sony or sgi. That GTE core can't only be used by sony there must be a processor using a GTE after 30 years. I still think i just haven't found it yet but with enough time maybe i will

Hope i don't get some kind of illness from that PDA i bought like covid, i got covid once it sucked, had me sick for over a month. That was over a year ago though haha There are other R3000 devices but they don't seem to have a graphics processor's

I don't know how long it will take to raise the money, I have looked into motherboard cloners, There seem to be a bunch of motherboard cloners or pcb cloners duplicators. Don't know how much they charge, There are also prototype builders. But i don't know if they can do what i need. When you google make obsolete cpu you get nothing. The whole thing is a big mystery. thinkin about downloading the tor browser and checking in the harder to reach places but in my experience the tor browser leads to computer vulerablity. I am committed to this project even if it isn't fruitful.

 

[Janus67]

You still haven't answered the question of what difference you are expecting with a higher clocked CPU. The games were all made for the current architecture (including ram), are you hoping for higher frame rates? Other than something which would lag under certain circumstances you aren't going to go from 30 to 60 fps.

Or are you just looking to waste your veteran pension on something?

Also, one last thing:

Witch = hag during Halloween or the Salem Witch Trials

Which = the word leading into another point.

 

[Kenrou]

On that note, is there a way to check if you can make it faster without breaking compatibility? Certain games/game engines were tied to clock speed and vsync (even newer ones like Days Gone), mess with those and the games will start acting out/crashing. I assume you're going for 1:1 compatibility with all PS1 games?

 

[winetime]

Sorry i meant which, thanks for the correction, good eye
As for my Veteran Pension, I won't spend beyond my means,
It won't be a waste at least to me, though it may seem that way to you

I am semi retired in a way, because i am 100% disabled by the VA, but i am still filing for disability through the state of California.
State of California still thinks i can work. I am filing an appeal with them in my case. I have invisible wounds witch are harder to explain to the state. The VA gets it though and took care of me. Long story short i had to contact the wounded warrior project and they filed a claim for me. Took me 10 years to seek help for my issues. Cause i wouldn't accept it. I have various serious mental health problems. That along with my bad knee now makes not much of anything for the work force you know. The state usually denies you the first time then you got to refile again like i am doing.

Or maybe i will take my broken self and try to work again. Never give up you know, don't quit. It would have to be a really simple non stressful job. I take anti psychotics daily to deal with my issues. Again the state doesn't get it you know. Thank God the VA and the state are completely separate from each other. One does not effect/affect the other.

When you don't work anymore you got to have hobbies, modding,painting and bicycle riding are mine

I started a go fund me fundraiser. I will use the money from that, if i raise enough, witch i don't think i will.

I would like the upgrade to yield better everything that it can. Again if i could i would recreate the entire thing and improve it. And offer upgrade boards. But got to start somewhere so i figure start with the cpu.

I used to overclock PS1s and sell them as a hobby. The Higher clocked cpu does improve frame rates but i only overclocked to about 40mhz. You can replace the clock generator and overclock it higher i believe but i have not done it myself so i am uncertain.

Have you seen the primitive linux running on the console. I think a higher clocked cpu would definitely help that situation

Anyway i hope i answered your questions. Again i am trying to raise 100 grand through go fund me. I really think the PS1 hardware would be the easiest to mod out of all the sony consoles.

 

[freeagent]

If Sony catches you tinkering with their stuff, couldn't they sue you into oblivion?

I would just go to Walmart or something and buy one of those 50K in one game boxes that look like the mini version. Plus it already has HDMI so you are good to go

 

[winetime]

If Sony catches you tinkering with their stuff, couldn't they sue you into oblivion?

I would just go to Walmart or something and buy one of those 50K in one game boxes that look like the mini version. Plus it already has HDMI so you are good to go

Not sure if sony could sue me. There patents have ran out. There trademarks have not. So i would have to ask a lawyer. Modders have been modding there consoles a long time and i never heard of anyone getting sued. Small time stuff i bet Sony doesn't sweat it. Good point though. I even thought about trying to ask Sony for some kind of permission but with patents expired i don't think i need it. Again i would have to consult a lawyer. I won't be trademarking anything that's for sure

 

[winetime]

Dawned on me late but i could simply take the Playstation 2s ps1 processor which is clocked at 36mhz. Its on the ps2 motherboard, not much of an upgrade though but an upgrade none the less