Questions on CT-ARM

[zxlee]

I had purchased a CT-ARM and was trying to learn how to use it. There are a few questions that I bumped into while using it, hopefully can get some guide/answer to it and also useful to other user.

1. Based on the datasheet of NUC131, the built in ADC was a 12-bit ADC. However, when I tried to use analogRead on one of the input, the max I could get is only 1023 when I connect it to the 5V, which is the max for a 10-bit ADC reading. For a 12-bit ADC, I am expecting to read something around 4095. So is the reading I get expected?

2. Based on the feature and specs, it is stated that there are 5+1 UART. May I know what is the 5+1 meant and which pins are the hardware UART pins?

Thanks

[bengchet]

Hi,

1. To use 12 bit ADC, simply insert analogReadResolution(12) at void setup() before you do any conversion. By default, the library uses 10 bit conversion. Argument in analogReadResolution(int res) refers to resolution, you can set any resolution you want within 1 to 12.

2. 5+1 UART means 5 hardwareSerial (can be used directly) and 1 hardwareSerial which can be used as well if some hardware modification is made(refers to Serial1).

HardwareUART
Serial - D0(RX) and D1(TX)
Serial1 - not used, initially it is intended for advanced users
Serial2 - D8(RX), D9(TX)
Serial3 - A4(RX), A5(TX)
Serial4 - SCL(RX), SDA(TX) Share the same pins as I2C
Serial5 - D10(RX), D11(TX)

FYI, the purpose of Serial1 is to allow serial debugging and connection of UART devices at the same time. Normally for most Arduino boards, if Serial is used for debugging, it cannot be used for hardware connection or vice versa. If proper modification is made, you can use Serial for debugging purpose only and Serial1 for hardware conneciton. If modified, Serial1 will use the same pins as Serial, D0 for RX and D1 for TX, and Serial will have nothing to do with these pins already.

[zxlee]

I just managed to try out the ADC, and yes it works, now I able to read using the 12-bit resolution. Thanks

[zxlee]

By the way, I found out that the CT-ARM pinout diagram from http://tutorial.cytron.com.my/2016/02/1 ... beta-test/ has mistake on pin labelling. The SPI pin on the header was labelled incorrectly, but luckily the silkscreen label was correct.

It would be nice too to have this pinout diagram in the user manual

[Idris]

By the way, I found out that the CT-ARM pinout diagram from http://tutorial.cytron.com.my/2016/02/1 ... beta-test/ has mistake on pin labelling. The SPI pin on the header was labelled incorrectly, but luckily the silkscreen label was correct.

It would be nice too to have this pinout diagram in the user manual

Hi zxlee, thanks for the feedback.