Forum Rule: Always post complete source code & details to reproduce any issue!
Tab Content
  • LenSamuelson's Avatar
    06-27-2021, 05:10 PM
    One API that I have wished to implement is to change from "disableInterrupts / enableInterrupts" to "curLevel = setPriority(newLeveli)"; one option for "newPri" should be "such a high priority that interrupts are...
    7 replies | 345 view(s)
  • LenSamuelson's Avatar
    06-22-2021, 03:17 AM
    Though your ISR is likely already cached given that it is probably being executed frequently in your tests, there are are some additional tools that may help with speed. About two thirds of the way down the Teensy...
    26 replies | 405 view(s)
  • LenSamuelson's Avatar
    06-21-2021, 02:24 AM
    I'm beginning to understand... you are not simulating ust a 27c256/27c512, you are simulating an 27c256/27c512 connected to a multiplexed address/data bus. That is a different animal... Are you planning to use only...
    26 replies | 405 view(s)
  • LenSamuelson's Avatar
    06-21-2021, 12:53 AM
    Given my continued interest in whether a Teensy can emulate an EPROM... Is your code changing the direction controls on the pins that serve as ADDRESS lines? For any addressed hardware component, its address signals...
    26 replies | 405 view(s)
  • LenSamuelson's Avatar
    06-20-2021, 07:01 PM
    Sounds like you're on your way. I've wondered for several years whether a Teensy could emulate an EPROM, considering the number of times my co-workers and I wished for rapid turnaround during development, so I hope you...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-19-2021, 06:32 PM
    You may want to consider how long OE# is expected to be active. If you are fairly confident that it is held active for limited time, then it may be OK to enter the ISR on OE# falling edge, then return from the ISR when...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-18-2021, 01:02 PM
    In case you have not found the code already... "avr" is basically a holdover from early days, but all teensy products are supported there. Two files you are likely to be interested in studying. I have found Paul's code...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-17-2021, 08:30 PM
    The discussion so far appeared to be related to 27c256 or 27c512 parts, which are just classical EPROMs, with nonmultiplexed address/data signals. So the discussion so far still fits the description. Your most recent...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-17-2021, 11:35 AM
    I wondered whether that was the case... edit: If you can count on your target pulsing OE# low for each access the logic is way simpler. If your target holds OE# low for a limited time interspersed with inactive...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-17-2021, 03:04 AM
    The RT106x processors are so fast that a well-written very tight interrupt service function triggered by the leading edge of OE# may be more likely to work properly than a DMA solution, and be a bit less complicated. ...
    28 replies | 585 view(s)
  • LenSamuelson's Avatar
    06-03-2021, 09:46 PM
    Is this a "spare no expense" project, or a "get the best results without going overboard" project? The ADCs in the Teensy 3.2 microcontroller can pull enough current during sampling that they appear to produce...
    4 replies | 399 view(s)
No More Results
About LenSamuelson

Basic Information

About LenSamuelson
Biography:
Mostly embedded, mostly comms
Location:
Ohio
Interests:
Cycling, home repair :-)
Occupation:
Developer (mostly embedded)

Statistics


Total Posts
Total Posts
109
Posts Per Day
0.04
Last Post
Backup the Interrupt Enable State and Restore it on the T4.x 06-27-2021 05:10 PM
General Information
Last Activity
Yesterday 02:28 PM
Join Date
08-24-2013