Search found 11 matches

by DrScanlon
Fri Jan 17, 2020 7:34 pm
Forum: General Discussion
Topic: bool volatile ????
Replies: 1
Views: 601

Re: bool volatile ????

Code: Select all

volatile bool system_passed = false;
bool volatile system_passed = false;
Both are correct.
by DrScanlon
Wed Sep 11, 2019 8:45 pm
Forum: General Discussion
Topic: esp32 developement board with external wifi antenna connection
Replies: 6
Views: 1771

Re: esp32 developement board with external wifi antenna connection

https://www.ezsbc.com/index.php/feature ... XlcZn97mY0

I have used the non-antenna boards from this vendor.
He is also good to work with if you need custom boards.

Frank
by DrScanlon
Sat Sep 07, 2019 4:36 pm
Forum: General Discussion
Topic: esp-idf httpd ethernet webserver performance is slow
Replies: 15
Views: 4372

Re: esp-idf httpd ethernet webserver performance is slow

I ran a quick test with a single 1.1MB file and got the following results using an 8K chunk size: Total read/send time: 4.6 secs, measured in ESP32 code. File read time (no sending): 2.24 secs Transfer testing was over wifi --> router --> gigabit network --> PC. ESP32 is about 5 ft from wireless rou...
by DrScanlon
Thu Sep 05, 2019 7:01 pm
Forum: General Discussion
Topic: esp-idf httpd ethernet webserver performance is slow
Replies: 15
Views: 4372

Re: esp-idf httpd ethernet webserver performance is slow

Just a couple of suggestions: 1. For the smaller files--smaller than your 10K chunk buffer--I would just send them in one step with content-length in response header. 2. If you are sending chunks based on the example given in file_server.c (under protocol examples),there is a problem in that code in...
by DrScanlon
Mon Aug 19, 2019 7:52 pm
Forum: General Discussion
Topic: Problem sending chunked response in Beta3 -- fileserver.c.
Replies: 0
Views: 544

Problem sending chunked response in Beta3 -- fileserver.c.

In Beta3 and ongoing development examples, in "protocols/.../file_server.c", a terminating chunk with chunksize = "0" is sent twice--once in the do-while loop and again in a closing line. This probably doesn't affect IExplorer, but Firefox (latest beta version) doesn't handle it well--frequently los...
by DrScanlon
Tue Jun 04, 2019 3:43 pm
Forum: General Discussion
Topic: 2d Array and pointers
Replies: 2
Views: 894

Re: 2d Array and pointers

I'm assuming C code. Something like the following should work: int arr[][2]={{11,12},{21,22},{31,32},{41,42},{51,52}}; int i,m,n,*j; // m=5; // n=2; // show(arr,m,n); void show (int *b,int l,int p) { int i,j; printf("show \n"); for(i=0;i<l;i++){ printf("%d %d \n",*(b+i*2+0),*(b+i*2+1)); } } void mai...
by DrScanlon
Sat Dec 08, 2018 5:41 pm
Forum: General Discussion
Topic: What would you like to see in The Next Chip?
Replies: 373
Views: 160650

Re: What would you like to see in The Next Chip?

Programmable sample time on the ADC.
by DrScanlon
Fri Oct 13, 2017 2:05 pm
Forum: General Discussion
Topic: VCC measurement with ADC via GPIO39
Replies: 4
Views: 6505

Re: VCC measurement with ADC via GPIO39

I'm not sure what is going on with the forum. I attempted to post a reply previously and I got logged out. About your measurement, I did a test using GPIO39 (ADC1 Channel 3) and found that 3.14vdc input resulted in 4095 counts. I decreased the voltage and saw a corresponding decrease in the AD count...
by DrScanlon
Fri Oct 13, 2017 12:19 am
Forum: General Discussion
Topic: VCC measurement with ADC via GPIO39
Replies: 4
Views: 6505

Re: VCC measurement with ADC via GPIO39

Hello, I just ran a test with ADC1_3. I used voltage ranges from 0 to 3.2vdc for input. Just for a quick test, I used the common power supply ground for the analog ground. I read 4095 counts at approx 3.14vdc. If I decrease the voltage, I see an expected drop in the counts. It appears to be function...
by DrScanlon
Wed Mar 29, 2017 8:44 pm
Forum: Hardware
Topic: ADC is very noisy
Replies: 0
Views: 1814

ADC is very noisy

I'm testing the adc1 for use in an application. With the 2V scale attenuation and using a 1.6 volt battery at the input, the average readings are about 860 or so. I'm aware of some linearity problems, but the main issue is that the readings from 660 to about 990. I am using the following code snippe...

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