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DrDnar wrote:
I actually get the impression that Zilog does not license the eZ80 design for incorporation into 3rd party chips. Nevertheless, assuming TI could work out a deal with Zilong, TI can switch to the eZ80 without changing much else in the ASIC, without changing the pinout of the ASIC, and without modifying any of their software, because the eZ80 is binary compatible with the Z80. Keeping the CPU speed still at 15 MHz, the eZ80 would make everything 4 times faster. If they made it 25 MHz, everything would be 6-10 times faster. And the eZ80 can be clocked up to at least 50 MHz.
Yes, I think that's one thing I didn't make totally clear in my review. I would be happy with a 25MHz z80, or a 15MHz ez80; a 25MHz ez80 would be extra icing on the cake.

Quote:
[...]An eZ80 upgrade would allow you to take fuller advantage of the new screen (e.g. full-resolution pictures, more graph colors, anti-aliased fonts), making everything prettier while still making the calculator much more responsive. You might even throw in 3D graphing.
Agreed heartily on the first part of that. I'm not overly discouraged about 3D graphing being partially possible with the current hardware, though, since I'm hoping I'll be able to port my Casio Prizm 3D graphing program to this calculator.
Can you test the speed of Output on the Homescreen? I'm curious how it compares to the 84+ and the 83+. On the old models, output is super fast.
Art_of_camelot wrote:
Can you test the speed of Output on the Homescreen? I'm curious how it compares to the 84+ and the 83+. On the old models, output is super fast.


TI-84+SE: 1000 outputs in 34.4 seconds
TI-84+CSE: 1000 outputs in 14 seconds

Not too shabby! The TI-84+CSE wins quite handily.

Edit: With MathPrint turned off, the TI-84+SE takes 7.2 seconds; oh well. Also, calc84 and I found that 6MHz is still the default for ASM programs executed by the OS, so my PCSEBall demo could actually get more like 70 FPS = 700 16x16 sprites per second instead of 30 FPS = 300 16x16 sprites per second. Also, as calc84 has reminded me many times, I haven't optimized yet.
Hmm... so it's about 2x slower. That isn't terrible. I wonder how it would do filling the entire homescreen though.
Art_of_camelot wrote:
Hmm... so it's about 2x slower. That isn't terrible. I wonder how it would do filling the entire homescreen though.
In other words, a 16*8-character string on the 84+SE versus a 26*10-character string on the 84+CSE? If so, I can easily test that too.

Edit: Optimizations and 15MHz mode brought it up to 120.8 FPS. That's a sweet 1208 sprites per second!
Yea, that's what I mean. I know updating the whole screen in ASM is a lot slower than updating a portion of it, so I was wondering if the homescreen behaved in a similar manner.
Kerm, for text, are there still some bugs causing extra rows of pixels to be erased? I think on MP OSes, when accessing the MODE menu, it enabled the last row of pixels for small fonts, for example.

For large fonts, I assume that not only the left-most column isn't erased, but the top as well?
Art_of_camelot wrote:
Yea, that's what I mean. I know updating the whole screen in ASM is a lot slower than updating a portion of it, so I was wondering if the homescreen behaved in a similar manner.
8.8 seconds for 10 full-screen Output(s on the TI-84+CSE, 7.9 seconds for *100* full-screen Output(s on the TI-84+SE. That's a much more telling story about pixel area.

DJ_O: A few finds:
1) Text( erases 2 pixels above and below in small-font mode
2) Text( erases 0 pixels left and 2 pixels right in small-font mode
3) Large Text( erases 0 pixels left, 0 above, 3(?) right, and 2 below
4) Going into the Mode menu changes none of this.
KermMartian wrote:
Yes, I think that's one thing I didn't make totally clear in my review. I would be happy with a 25MHz z80, or a 15MHz ez80; a 25MHz ez80 would be extra icing on the cake.


A 25MHz ez80 would make all the difference between a Ti 84+SE with a sluggish-16 bit color screen and a 50+MHz spiffy calculator with a fast LCD, 128KB RAM, 4MB ROM, and a possible native 3D graphing engine w/ CAS.
It's not _that_ sluggish, only if you're trying to write complex games. For math and science, it's a very capable and responsive calculator.

For my ASM brethren: Discovered playing around with my TI-84+CSE during HCWP:
1) You can output the same byte as the high and low byte to port $10 and it will ignore the high byte. This is a useful optimization.
2) I was able to read LR:$03 back in, which will be very handy for restoring settings after a program runs
3) I was also able to read LR:$00, which returned 37685d = 9335h: We actually have an ILI9335 controller, not ILI9325 (new datasheet). This isn't actually any sort of substantive change.
KermMartian wrote:
Art_of_camelot wrote:
Yea, that's what I mean. I know updating the whole screen in ASM is a lot slower than updating a portion of it, so I was wondering if the homescreen behaved in a similar manner.
8.8 seconds for 10 full-screen Output(s on the TI-84+CSE, 7.9 seconds for *100* full-screen Output(s on the TI-84+SE. That's a much more telling story about pixel area.


Yikes! That is bad! I was afraid this was going to be the case. Sad
Yup, sad but true, a result of having to update (320*(240-30)) pixels per each of those Output( commands compared with a mere 96*64-ish. That's 10.94 times as many pixels, so a 10x slowdown makes sense.
KermMartian wrote:
Art_of_camelot wrote:
Can you test the speed of Output on the Homescreen? I'm curious how it compares to the 84+ and the 83+. On the old models, output is super fast.


TI-84+SE: 1000 outputs in 34.4 seconds
TI-84+CSE: 1000 outputs in 14 seconds

Not too shabby! The TI-84+CSE wins quite handily.

Edit: With MathPrint turned off, the TI-84+SE takes 7.2 seconds; oh well. Also, calc84 and I found that 6MHz is still the default for ASM programs executed by the OS, so my PCSEBall demo could actually get more like 70 FPS = 700 16x16 sprites per second instead of 30 FPS = 300 16x16 sprites per second. Also, as calc84 has reminded me many times, I haven't optimized yet.



Woah, how'd I miss that demo? That's really cool!
Thanks, Elfprince13. I'm hoping to publish a summary article of sorts tonight that mentions a few things:

- Support for the new .8xi format in SourceCoder
- jsTIfied TI-84+CSE support
- Slashdot and Gizmodo reposts of my review
- My ASM PCSEBall demo and BASIC Frogger demo
- Adriweb's lowercase program

Did I miss anything?
KermMartian wrote:
Art_of_camelot wrote:
Can you test the speed of Output on the Homescreen? I'm curious how it compares to the 84+ and the 83+. On the old models, output is super fast.


TI-84+SE: 1000 outputs in 34.4 seconds
TI-84+CSE: 1000 outputs in 14 seconds

Not too shabby! The TI-84+CSE wins quite handily.

Edit: With MathPrint turned off, the TI-84+SE takes 7.2 seconds; oh well. Also, calc84 and I found that 6MHz is still the default for ASM programs executed by the OS, so my PCSEBall demo could actually get more like 70 FPS = 700 16x16 sprites per second instead of 30 FPS = 300 16x16 sprites per second. Also, as calc84 has reminded me many times, I haven't optimized yet.
Sounds good, although it's a shame that colors can't be used on the home screen. (At least on the PRIZM they could and it was actually fast)
Yeah, that is a real shame. We can sort of fake it using Text(-1 on the graphscreen, but not for vertical-scrolling BASIC games. By the way, I see that Ryan (Phero) got his hands on a TI-84+CSE and posted a speed test over at ticalc.org (although I'm sorry to say I criticized his methodology). Sad
Personally im kind of 50/50 about my feelings towards the hardware. On one hand it would be nice to have a more powerful CPU, on the other im VERY glad that the challenge of pushing low-end hardware to its limits has not disappeared Smile.
tr1p1ea wrote:
Personally im kind of 50/50 about my feelings towards the hardware. On one hand it would be nice to have a more powerful CPU, on the other im VERY glad that the challenge of pushing low-end hardware to its limits has not disappeared Smile.
I think that very challenge might re-capture the interest of a lot of older and more experienced calculator programmers who got bored of working with the existing TI-83 Plus/TI-84 Plus-family calculators. That's my hope, anyway; we'll see if it pans out.
So, how did the gameboy color manage to support a big screen with color without being slower than a slug?
NanoWar wrote:
So, how did the gameboy color manage to support a big screen with color without being slower than a slug?
Welcome back, NanoWar. Based on reading a few technical articles about the Gameboy Color to answer your question, the answer is three-fold:
1) Lower resolution (160x144) means 2/3 fewer pixels than a 320x240 LCD
2) Palettized display: you don't pipe 15-bit values to the LCD. It seems you instead send 4, 5, or 6-bit values packed together.
3) Some sort of hardware sprite/tilemapping support, based on:
Wikipedia wrote:
Maximum sprites: 40 total, 10 per line, 4 colors per sprite (one of which being transparent)
Sprite size: 8x8 or 8x16
Tiles on screen: 512 (360~399 visible, the rest are drawn off screen as a scrolling buffer)
  
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