Search found 12 matches

by bscholte
Wed Dec 04, 2019 10:19 am
Forum: Cortex-M3
Topic: Using System Tick
Replies: 4
Views: 2851

Re: Using System Tick

The posted Module works like a charm and frees up a Timer. Thanks!

The only difference for my LCP1769 at 120MHZ and a tick every 10mSec, is the RELOAD. The value given in the manual (120MHZ/100 - 1= 1199999) nicely produces the desired tick.

Cheers!
by bscholte
Fri Nov 29, 2019 7:53 am
Forum: Cortex-M3
Topic: Using System Tick
Replies: 4
Views: 2851

Re: Using System Tick

The article has more information than the NXP LPC manual, so it does help. In the LPC manual, the information is partly in the main section, but critical details are in the ARM section. For example, the NVIC offset vector seems to be at $3C, which is below the $40 that is the lowest in the NXP NVIC ...
by bscholte
Thu Nov 28, 2019 7:32 pm
Forum: Cortex-M3
Topic: Using System Tick
Replies: 4
Views: 2851

Using System Tick

We are building an "RTOS" an a LPC-1769-ARM3 and are using the standard Timer module, using Timer3 for a 10mS pulse which basically clocks everything. Following the documentation, the System Tick should do exactly the same thing. So, we thought it would be easy to convert the Timer module into a Sys...
by bscholte
Tue Apr 16, 2019 7:58 am
Forum: Cortex-M3
Topic: Setting Baud rates in Serial
Replies: 1
Views: 2527

Setting Baud rates in Serial

To communicate to several peripheral devices, I needed different baud rates. After building a brief spreadsheet based on the LPC manual, I optimized a list of settings for my target (LPC1769 with MCU.PCLK=30MHZ). BaudRate DLM DLL DIVADDVAL MULVAL 1200 6 27 0 1 2400 3 13 0 1 4800 1 135 0 1 9600 0 195...
by bscholte
Sun Aug 12, 2018 12:11 pm
Forum: Cortex-M3
Topic: Logic operations
Replies: 5
Views: 9514

Re: Logic operations

Wow. Very elegant! Thanks.
by bscholte
Fri Aug 10, 2018 3:35 pm
Forum: Cortex-M3
Topic: Logic operations
Replies: 5
Views: 9514

Re: Logic operations

To be (hopefully) complete, a short module to implement common logic ops. MODULE Logic; PROCEDURE* And*(A, B:INTEGER):INTEGER; (*e.g. 5 AND 3 = 0101 AND 0011 = 0001 = 1*) BEGIN RETURN ORD(BITS(A) * BITS(B)) END And; PROCEDURE* Or*(A, B:INTEGER):INTEGER; (*e.g. 5 OR 3 = 0101 OR 0011 = 0111 = 7*) BEGI...
by bscholte
Fri Aug 10, 2018 11:41 am
Forum: Cortex-M3
Topic: Logic operations
Replies: 5
Views: 9514

Re: Logic operations

Excellent! That works and is actually easier. As suggested, I used the BITS() to cast from integer to set and ORD() to cast back. The rest is arithmetic on sets. A small module to test the workings. Not tested thoroughly, but.... (Below are the "Out.Bits" and "Out.Bool" to show the results). MODULE ...
by bscholte
Tue Aug 07, 2018 9:06 am
Forum: Cortex-M3
Topic: Logic operations
Replies: 5
Views: 9514

Logic operations

During application development I frequently encounter the need to do logic operations on bytes or numbers (AND, OR, XOR, NOT). For each of these, there are assembler instructions and most programming languages have these implemented in some form. Since I haven't found a better way, I currently get b...
by bscholte
Sun Jun 25, 2017 3:50 pm
Forum: Development Boards
Topic: New target
Replies: 2
Views: 15596

Re: New target

On your related note: Yes there is. Please check our (progressing) web page at http://www.psysengineering.com/oberon or contact us directly at info@psysengineering.com.

Bart
by bscholte
Sat Feb 14, 2015 10:57 am
Forum: Cortex-M3
Topic: Read a micro SD card using MMC / SPI
Replies: 5
Views: 25168

Re: Read a micro SD card using MMC / SPI

Dear all, For compatibility reasons, I decided to implement the FAT16 file system. Completely based on the modules that were published in the first article of this post. It is working quite well and also very old (32MB) card with very fragmented files can be red. I have not attached the code yet bec...