Matrix Orbital GLK24064-25 Legacy User Manual

Page 15

Figure 14: Power Connector

Table 5: Connector Pinout

Pin 4

Ground

Pin 3

SDA (I

C data)

Pin 2

SCL (I

C clock)

Pin 1

Vdc

The display does not work on I

C by default. The modification shown below must be done;

Figure 15: I

2.2.5 ACK

The idea of ACK is to indicate when the data has been received correctly. ACK does not indicate data

incorrectly received. ACK simply fails to indicate when data is correctly received. Clearly, this is of limited

usefulness and even less so with Matrix Orbital modules. Matrix orbital modules are not capable of failing

to acknowledge and incorrectly received byte in response to that bytes transition. They are only capable of

failing to acknowledge the bytes following the byte, which was not received. To fully understand the reasons

for this one needs to understand something about how a Matrix Orbital module processes data. Basically the

reason why a Matrix Orbital module might fail to receive a byte correctly is that it was unable to process the

byte previous before the failed byte was transmitted. Because the module cannot possibly know that it would

be unable to store the byte before the next byte was received it cannot know to not ACK. The reason for this

situation in deference to situations one might be familiar with (i.e., memory chips, etc) is that the Matrix

Orbital module employs a micro-processor to perform these data storage functions. A memory chip takes

Matrix Orbital

GLK24064-25