How to read directly from Serial1? (baby steps into CASIC)

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•

HughB
The doc say id << 24, but when its goes through the different msg types it always puts class followed by id together in every table. Its a bit confusing and easy to read the check sum as class << 24 when in fact its msg_id << 24.

It looks to me like the initial part of the chksum calc is done as:
```
sum = (msg_id << 24) + (msg_class << 16) ++ (len_byte1 << 8) + (len_byte0)
```
which matches the doc:
```
//The calculation of the check value can follow the following algorithm:
ckSum = (id << 24) + (class << 16) + len;
for (i = 0; i <(len / 4); i++)
{
    ckSum = ckSum + payload [i];
}
```
In this instance msg_id is 0x01, msg_class is 0x0B
The length is 0x0038 or 0x38 = 56 decimal bytes which is the size of the payload buffer.
As per screenshot below - the msg class and msg id are shown in that order in every part of the doc

•

Mark_M in reply to @HughB

My doc v3.6 on pg 27 says:

ckSum = (class << 24) + (id << 16) + len;
for (i = 0; i <(len / 4); i++)
{
ckSum = ckSum + payload [i];
}

But the same doc v4.2 from the site says

ckSum = (id << 24) + (class << 16) + len;

confusing!

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