lpcware

AD0 in BURST mode on LPC1347 - Query

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by mathseng on Wed Jan 08 20:51:18 MST 2014
Hi,
I'm using the ADC project from "LPCXpresso Example Projects and CMSIS library for LPC1315_16_17_45_46_47  2013-01-16 17:57  v1.01" (from this site - LPC13xx Software Downloads)  and am getting differing results for AD0 when using Polled and Burst mode conversion, with the Burst mode AD0 value being definitely incorrect.

When using BURST mode, I am getting results similar to the value in "some other ADC", and the value varies depending on the number of other ADC inputs I am converting. AD1..AD7 (excluding AD4 - used for SWDIO) all give consistent and apparently correct values.
When using POLLED or POLLED Interrupt mode, I get consistent and apparently correct values for ALL ADC inputs.

Has anyone else met this issue? If so, have you solved it?
(Note: this code does not use the GDR, so complies with Errata doc)

Regards,
Bill

configuration:
LPCXpresso LPC1347 Rev A.
protoboard with a number of 2k potentiometers (plus other components to make a simulator for my project)
LPCXpresso IDE 5.x - 6.x

Code Changes
adc.h: ADC_INTERRUPT_FLAG
adc.h BURST_MODE

adctest.c
remove "while 1" from test blocks
     if ( OverRunCounter != 0 )

adctest.c
changed uart inclusions:
#if ADC_DEBUG
//#include "uart.h"
#define UARTSend(x, j)
#define UARTInit(x)
#endif

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