Maximum Max7219 Modules

[Synology-John]

I am attempting to use your library but it seems to top out at 16 modules. I have 20 modules connected The arduino is powered from the display, not the other way round

Displays set to 5 I get 4 x 5 modules working Displays set to 10 I get 2 x 10 modules working Displays set to 15 I get 1 x 15 + 1 x 5 modules working Displays set to 16 I get 1 x 16 + 1 x 4 modules working Displays set to 17 I get 1 x 16 + 1 x blank + 3 x modules working Displays set to 20 I get 1 x 16 modules working + 4 x blank. This is testing with the simple Ticker script. Is this to do with your library or the Adafruit_GFX library I am only just learning arduino so not very experienced. Any help would be appreciated Thanks

[petervflocke]

Sorry for long delay. The clock works and I did not check my "developer corner" for a long time. I did not get you. What does it mean "Displays set to 5 I get 4 x 5 modules working"? You have to set up an array of displays. 4x5 = 20 displays not 5

int numberOfHorizontalDisplays = 4;
int numberOfVerticalDisplays = 5;

Furthermore I would assume that if there is a problem it is related to my library not to GFX. The latter is well tested :)

What arduino board do you use? Are you sure the electrical connection are fine? Enough current to supply, etc. ..

I tested this with ESP32 - a lot of memory, in case of small atmel microcontrollers there might be a memory issue.

[Synology-John]

Hi Peter

Thanks for getting back to me.

The problem has been resolved.

The problem was the maximum number of modules the max7219panel library would support.

Originally the library would only support 16 modules

After the library was edited (line 106) changed from int8_t to int16_t

It now works with more than 16 modules without error

John

From: petervflocke [mailto:notifications@github.com] Sent: 07 November 2018 00:25 To: petervflocke/ESP32MatrixClock Cc: Synology-John; Author Subject: Re: [petervflocke/ESP32MatrixClock] Maximum Max7219 Modules (#2)

Sorry for long delay. The clock works and I did not check my "developer corner" for a long time. I did not get you. What does it mean "Displays set to 5 I get 4 x 5 modules working"? You have to set up an array of displays. 4x5 = 20 displays not 5

int numberOfHorizontalDisplays = 4; int numberOfVerticalDisplays = 5;

Furthermore I would assume that if there is a problem it is related to my library not to GFX. The latter is well tested :)

What arduino board do you use? Are you sure the electrical connection are fine? Enough current to supply, etc. ..

I tested this with ESP32 - a lot of memory, in case of small atmel microcontrollers there might be a memory issue.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/petervflocke/ESP32MatrixClock/issues/2#issuecomment-436458586 , or mute the thread https://github.com/notifications/unsubscribe-auth/AnJ_-iUmkgsXN8eMUzLXWQ7K5grg6Z-pks5usihAgaJpZM4VgDxl . https://github.com/notifications/beacon/AnJ_-tfIMjY_Opb64MJP4O-nialvQbH6ks5usihAgaJpZM4VgDxl.gif

[Synology-John]

Hi Peter

Just looking at your code in the library ppmax7219panel.cpp

Line 124 is int8_t x = xx; this would limit the maximum number of modules in one row to 16

If it is changed to int16_t x=xx; this removes this limit

John

From: petervflocke [mailto:notifications@github.com] Sent: 07 November 2018 00:25 To: petervflocke/ESP32MatrixClock Cc: Synology-John; Author Subject: Re: [petervflocke/ESP32MatrixClock] Maximum Max7219 Modules (#2)

Sorry for long delay. The clock works and I did not check my "developer corner" for a long time. I did not get you. What does it mean "Displays set to 5 I get 4 x 5 modules working"? You have to set up an array of displays. 4x5 = 20 displays not 5

int numberOfHorizontalDisplays = 4; int numberOfVerticalDisplays = 5;

Furthermore I would assume that if there is a problem it is related to my library not to GFX. The latter is well tested :)

What arduino board do you use? Are you sure the electrical connection are fine? Enough current to supply, etc. ..

I tested this with ESP32 - a lot of memory, in case of small atmel microcontrollers there might be a memory issue.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/petervflocke/ESP32MatrixClock/issues/2#issuecomment-436458586 , or mute the thread https://github.com/notifications/unsubscribe-auth/AnJ_-iUmkgsXN8eMUzLXWQ7K5grg6Z-pks5usihAgaJpZM4VgDxl . https://github.com/notifications/beacon/AnJ_-tfIMjY_Opb64MJP4O-nialvQbH6ks5usihAgaJpZM4VgDxl.gif

[petervflocke]

The problem has been resolved.

Perfect! Good Job! Best Regards