topic MCF5329 LCDC as GPIO in ColdFire/68K Microcontrollers and Processors

MCF5329 LCDC as GPIO

JD1z — Mon, 15 Apr 2013 10:43:58 GMT

I want to use the LCDC LD0 and LD1 as GPIO output pins.

From reading the 5329 ref manual, they default to GPIO and configured as inputs..

But I have configured it for GPIO anyway. I can set and clear LD0 but

can't seem to do anything with LD1.

I have used the following code to configure and drive.

VMCF5329_GPIO_STRUCT_PTR gpio = &((VMCF5329_STRUCT_PTR)_PSP_GET_IPSBAR())->GPIO;

gpio->PAR_LCDDATA = 0; //configure as GPIO

gpio->PDDR_LCDDATAL = 0x03; //LD0 and LD1 as output

gpio->PPDSDR_LCDDATAL = MCF5329_GPIO_PPDSDR_x0 || MCF5329_GPIO_PPDSDR_x1; //to set LD0 & LD1

gpio->PCLRR_LCDDATAL = MCF5329_GPIO_PCLRR_x0 || MCF5329_GPIO_PCLRR_x1; // to clear LD0 & LD1

I have also tried

gpio->PODR_LCDDATAL = 0x0;

gpio->PODR_LCDDATAL = 0x3;

I can see LD0 changing state but not LD1. Not sure what I doing wrong or missed anything out.

Note : I have not done anything with drive strength.

Thanks

Re: MCF5329 LCDC as GPIO

TomE — Mon, 15 Apr 2013 23:41:06 GMT

From the manual that should work. I have an MCF5329 here on a board, connected to a video chip. It doesn't have LD0 connected, but it does have LD1 connected to the video, and I can see the effect of writing LD1 as a GPIO. I'm using GDB through a P&E Multilink:

(gdb) x/b 0xfc0a405d          # LCD Pin Assignment Register
0xfc0a405d:     0xff             # Set to LCDC
(gdb) set *(uint8_t *)0xfc0a405d = 0xfc # LCD Pin Assignment Register, set LD0-LD7 as GPIO
(gdb) set *(uint8_t *)0xfc0a4023 = 0x03 # LCD PDDR, LD0, LD1 as output.
(gdb) set *(uint8_t *)0xfc0a400f = 0x00 # All pins low
(gdb) set *(uint8_t *)0xfc0a400f = 0x02 # LD1 high

I'd check that the macros you're using are generating the right addresses.

I'd also read back the registers in a debugger - and set them in the debugger too.

It may be a hardware problem. Change LD1 to an input and see if you can send signals into that pin.

Tom

Re: MCF5329 LCDC as GPIO

JD1z — Tue, 16 Apr 2013 09:43:47 GMT

Hi Tom

Just tried the addresses rather than the macros. It still behaves the same way.

Added a line to show the current status of the port, from this I could see LD1 was always 0.

I checked the modifications carried out and found that LD1 was shorted to gnd. Once

this was sorted all worked as expected.

Thanks

Jaswinder