topic Re: LPC1517 project in LPC Microcontrollers

LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:48 GMT

Content originally posted in LPCWare by bobi-one on Fri Mar 28 04:35:24 MST 2014
Hi,
I am creating lpc1517 design, and wonder if this configuration will be enough to make it running. Reset shall be used for SWD only. And DAC and ADC wont be used in this configuration.
If you have any suggestions please guide me in the design process.
Regards,
Boyko

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:49 GMT

Content originally posted in LPCWare by LabRat on Fri Mar 28 05:34:31 MST 2014
ISP_0 :quest:
ISP_1 :quest:

Your 1517 has USB? Where do you buy them :)

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:49 GMT

Content originally posted in LPCWare by bobi-one on Fri Mar 28 05:41:29 MST 2014
Oh my bad I am using the same symbol for both ( 1549 abd 1517) but for now I don't need usb capabilities.
What are those ISP signals? Are they essential for working with my custom board and the LPClink?
There is button on the Official board , but I am not aware for its purpose.
Regards,
Boyko

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:50 GMT

Content originally posted in LPCWare by LabRat on Fri Mar 28 06:06:29 MST 2014
:quest:

In-System Programming (ISP):

UM:

Quote:

5.3 Pin description
The parts support ISP via the USART0, C_CAN, or USB interfaces. The ISP mode is
determined by the state of two pins at boot time:
The ISP pin assignment is different for each package, so that the fewest functions
possible are blocked. No more than four pins must be set aside for entering ISP in any
ISP mode. The boot code assigns two ISP pins for each package which are probed when
the part boots to determine whether or not to enter ISP mode. Once the ISP mode has
been determined, the boot loader configures the necessary serial pins for each package.
UM10736
Chapter 5: LPC15xx Boot process
Rev. 1 — 13 February 2014 User manual
Table 89. ISP modes
ISP mode[color=#0f0] ISP_0 ISP_1[/color] Description
No ISP [color=#0f0]HIGH HIGH[/color] ISP bypassed. [color=#f00]Part attempts to boot from flash.[/color]
If the part is not programmed or contains invalid user
code, this mode will enter ISP via USB.

C_CAN[color=#0f0] HIGH LOW[/color] [color=#f00]Part enters ISP via C_CAN[/color].
USB[color=#0f0] LOW HIGH[/color][color=#f00] Part enters ISP via USB[/color].
USART0[color=#0f0] LOW LOW[/color] [color=#f00]Part enters ISP via USART0[/color].

This two pins are selecting a bootloader (UART/USB/CAN).

So if you connect a LED to one of this pins, it's low and you are starting a bootloader!!

Therefore it's useful to add a jumper to GND and pull these pins up (10k)...

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:50 GMT

Content originally posted in LPCWare by mc on Fri Mar 28 07:18:00 MST 2014
Hi Boyko,
ISP functionality is very useful to update firmware in the chip without requiring Serial Wire Debugger (SWD) debugger. For example, if you use USB ISP (first press and hold ISP0 switch SW3 and then press and release reset switch SW4 on LPC1549 Xpresso board) when USB (Micro connector J3 on LPC1549 Xpresso board) is connected to PC will create a drive on the PC. You can delete firmware.bin file from this drive and copy binary file generated by you. When you reset board (SW4 on LPC1549 Xpresso board), your updated firmware is now running on this board.

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:51 GMT

Content originally posted in LPCWare by bobi-one on Fri Mar 28 07:45:51 MST 2014
Thank you for the quick answer.
So PIO0_4(ISP0) and PIO0_16(ISP1) must not be used by my peripheral.
In order to make my board as small as possible I took out SWDIO /SWCLK/ RESET/GND/3,3V to a connector. Which I intend to program with the LPCLink.
Therefore what will be the most user frendly method of doing so, without using buttons and jumpers on the board. I am not completely sure how SWD runs both if bot ISP pins are HIGH will SWD work ?
Regards,
Boyko

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:52 GMT

Content originally posted in LPCWare by LabRat on Fri Mar 28 07:51:18 MST 2014

Quote: mc
... create a D: drive on the PC

OMG, my 1549 is damaged. It's always creating a F: drive :O Sooner or later.

But seriously, that's very slow. On my W8.1 PC it takes about 50 seconds until it shows the new drive. So don't panic too early...

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:52 GMT

Content originally posted in LPCWare by LabRat on Fri Mar 28 07:59:36 MST 2014

Quote: bobi-one
I am not completely sure how SWD runs both if bot ISP pins are HIGH will SWD work ?

Usually without problems :)

You can debug/ flash your LPC with SWD (ISP_0 / ISP_1 both high). If that fails or if you want to flash with a bootloader, then you pull down the required ISP pin(s)...

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:53 GMT

Content originally posted in LPCWare by bobi-one on Fri Mar 28 08:07:37 MST 2014
So in my case if put dummy resistors to ground and populate them only in worse case scenario and if both inputs are hanging ( no pull up like on the lpcxpresso board) that will work just fine?

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:54 GMT

Content originally posted in LPCWare by LabRat on Fri Mar 28 08:31:16 MST 2014

Quote: bobi-one
So in my case if put dummy resistors to ground and populate them only in worse case scenario and if both inputs are hanging ( no pull up like on the lpcxpresso board) that will work just fine?

Wouldn't recommend that. External Reset and ISP pull-ups are very useful and I've seen to much 'surprising behavior' of boards without them. A small 402 pull-up and another 402 (not populated) as jumper are a damned good insurance...

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:55 GMT

Content originally posted in LPCWare by MarcVonWindscooting on Sun Mar 30 13:38:52 MST 2014
Hey Boyko,

I doubt a 100k resistor is a suitable supply for VDDA.

If you don't use AD/DA, then you don't need the decoupling caps - connect directly to VDD.
If you use AD/DA then these units consume around 100uA..800uA.

If I were you I would sacrifice one LED and use DAC_OUT for driving a piezo speaker. This allows you to mix several sound sources easily - which is way better than digital drive, only.

Marc

Re: LPC1517 project

lpcware — Wed, 15 Jun 2016 17:03:55 GMT

Content originally posted in LPCWare by bobi-one on Sun Mar 30 23:36:22 MST 2014
Hi I am connecting an external 16bit DAC to the second SPI ( 1st one is for the MMC) so i could produce kind-of high quality 16bit sound.
the 100k resistor is just for the pads and I would probably remove those decoupling caps in the final version of the board.
Regards,
Boyko