Coming Soon: Teensy-LC (low cost Teensy)

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KurtE said:
Also my built table could be wrong, but wondering about PWM on pin 21?
Click to expand...

based on core_pins.h, i think your table is spot on, though you need to color pin 22 PWM (TPM0_CH0)

Code: 
#define CORE_PIN0_CONFIG    PORTB_PCR16
#define CORE_PIN1_CONFIG    PORTB_PCR17
#define CORE_PIN2_CONFIG    PORTD_PCR0
#define CORE_PIN3_CONFIG    PORTA_PCR1
#define CORE_PIN4_CONFIG    PORTA_PCR2
#define CORE_PIN5_CONFIG    PORTD_PCR7
#define CORE_PIN6_CONFIG    PORTD_PCR4
#define CORE_PIN7_CONFIG    PORTD_PCR2
#define CORE_PIN8_CONFIG    PORTD_PCR3
#define CORE_PIN9_CONFIG    PORTC_PCR3
#define CORE_PIN10_CONFIG   PORTC_PCR4
#define CORE_PIN11_CONFIG   PORTC_PCR6
#define CORE_PIN12_CONFIG   PORTC_PCR7
#define CORE_PIN13_CONFIG   PORTC_PCR5
#define CORE_PIN14_CONFIG   PORTD_PCR1
#define CORE_PIN15_CONFIG   PORTC_PCR0
#define CORE_PIN16_CONFIG   PORTB_PCR0
#define CORE_PIN17_CONFIG   PORTB_PCR1
#define CORE_PIN18_CONFIG   PORTB_PCR3
#define CORE_PIN19_CONFIG   PORTB_PCR2
#define CORE_PIN20_CONFIG   PORTD_PCR5
#define CORE_PIN21_CONFIG   PORTD_PCR6
#define CORE_PIN22_CONFIG   PORTC_PCR1
#define CORE_PIN23_CONFIG   PORTC_PCR2
#define CORE_PIN24_CONFIG   PORTE_PCR20
#define CORE_PIN25_CONFIG   PORTE_PCR21
#define CORE_PIN26_CONFIG   PORTE_PCR30
 
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KurtE said:
but wondering about PWM on pin 21?
Click to expand...

I agree pin 21 is NOT PWM , but 20 is PWM. here are channel assignments

#define FTM0_CH0_PIN 22
#define FTM0_CH1_PIN 23
#define FTM0_CH2_PIN 9
#define FTM0_CH3_PIN 10
#define FTM0_CH4_PIN 6
#define FTM0_CH5_PIN 20
#define FTM1_CH0_PIN 16
#define FTM1_CH1_PIN 17
#define FTM2_CH0_PIN 3
#define FTM2_CH1_PIN 4
 
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Yes, good catch. Pin 21 was mislabled. The PWM was meant to be on pin 20. The DAC pin also has a copy-n-paste error of "17".

I'm planning to use much otherwise empty space on the back side to specify the per-pin current and interrupts. I hope to have a first draft tonight or early tomorrow.
 
Another draft.

card6a_rev1.jpg
 
manitou said:
On 3.* cards, pin between Vin and 3.3v was marked as AGND

and shouldn't A12/DAC be 26 not 17?

the red dots for 20ma pins was nice addition as per Nantonos draft, though I guess your bold for 5,16,17,21 conveys that info (steganography)
Click to expand...

what about AGND ?
 
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your pin table in the first posting of this thread shows INT on pin 2, your card does not ...

#define CORE_INT2_PIN 2

otherwise, your back side looks fine.:(
 
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Nice part of the product.

This could make pin 17 on back harder to misinterpret, and the same has room on the front as well.
LC_Back_17.png

This arrangement would show fewer top row color jumps
LC_Front_Order.png
 
Congrats Paul!

I preordered a couple on general principles. The Teensy is just so darned versatile though, and it handles project feature creep perfectly.
 
Looking at the card reminded me of something when I last went to my electronics toy-stores that both sell Teensy 3.1 (You-do-it in Needham, MA, and Microcenter in Cambridge, MA). In both of these stores, they have a wall of various bits and pieces, and several microprocessors (Sparkfun red boards, Adafruit Trinkets/Gemmas, Digisparks, Raspberry Pis, etc.). Interestingly, both stores have very few Arduino branded boards, though various clones.

The card mentions the http://www.pjrc.com/teensy link on the front and the http://www.pjrc.com/help link on the back, which is great (and more than some of the vendors list). But if you go to the teensy site, it dives straight into pictures of the Teensy boards with pin layouts, etc. And then it goes into older products that may be near their end of life.

It strikes me that it doesn't help users who are coming to Teensy fresh, and have not been programming Arduinos and other processors for years if you started with the basics of what you can do with the processor, giving links to a few examples (blink, neopixel, etc.).

Now, I realize you've been running full tilt getting LC out the door, and having Arduino 1.6.0 dropped on top of you, but it may make sense to revisit the main page to make it more friendly to newcomers when you get a chance to breathe. And even for non-newcomers, it may be useful to put in links for things like octows2811, audio shield, etc. I know there have been several attempts at making things more friendly, including https://forum.pjrc.com/threads/25395-Teensy-Quick-Reference-Code-Examples-Tips-and-Tricks, but I'm not sure what can be done.
 
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I am not sure if it maters, but my spreadsheet I posted print out of, I think, pins 24, 25 on back also can be used for TX1, RX1?
 
Yes, they can. Maybe on the next rev of the card, I'll cram more stuff into that part.

Those lines with arrows are a problem though. Maybe there's a better way to show this?

It's going into this print shop today, so we'll have cards next week. Any more edits will need to go onto the next printing.
 
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I can't wait to get my cards in the mail! - with the LC pair I felt compelled to order. Cool color alignment :) - I thought the box idea was better. Maybe I'll hook up the one LC for a serial debug terminal with a ILI9341 screen and add in the tiny_scope code.
 
I should confess, this first batch of cards will be "digital press", which lacks the color quality of "offset press" printing we normally use.

The reason is digital press printing is fast, only a couple days (and they offset same day service for an extra fee). The last thing I want is to be waiting on printed cards when boards are ready next week.

Future batches will be done with the higher quality offset press printing.
 
manitou said:
tell me more. are you using INPUT_PULLUP on teensy side? how fast is input signal changing? what is source of 5v signal?
Click to expand...

The 5v signal is from a ks0108 GLCD.
Depending on what is happening the 8 GLCD data pins can be inputs or outputs.

I hooked up the analyzer and my h/w delays are the same for both Teensy 3.0 vs Teensy LC.
Typical delays are between 140ns and 500ns depending on the type of operation.
(actual delays are a little bit longer due to what is possible given the CPU clock and instruction cycles)
Those values are defined by the ks0108 spec.

I have tried both INPUT and INPUT_PULLUP with no change.
The current code self adjusts for various environments (AVR, PIC32, ARM) and has been
working for several years.

With Teensy 3.0 it can reliably read the 5v inputs when 10k series resistors are used on the GLCD data lines.
Teensy LC has issues with the 10k series resistors but works fine when the 8 data lines are properly level shifted
using a TI TXB0108 level shifter.

Because it reliably works when a real level shifter is used, I'm tending to rule out a s/w issue.

I don't have a scope so I can't look to see if there is any sort of ringing or slew rate issues
on the signals.

Not sure what the difference is between the internal i/o pin h/w on the Teensy 3.0 vs the Teensy LC but
they don't appear to working the same in this case.


I was hoping to be able to cheat on the 5v input mapping on the Teensy LC the same as what
could be done on the Teensy 3.0

I'm kind out of ideas on what to look at or try next.
Anybody got any ideas?

I guess it might be useful to look at the datasheet for the part
to compare the i/o specs to the part used on the Teensy 3.0

Anybody got pointers to the two datasheets?


--- bill
 
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