Datasheet

VS1053b Datasheet
10 OPERATION
10.11 Extra Parameters
The following structure is in X memory at address 0x1e02 (note the different location than in
VS1033) and can be used to change some extra parameters or get useful information.
Notice that reading two-word variables through the SCI_WRAMADDR and SCI_WRAM inter-
face is not protected in any way. The variable can be updated between the read of the low and
high parts. The problem arises when both the low and high parts change values. To determine
if the value is correct, you should read the value twice and compare the results.
The following example shows what happens when is decreased from 0x10000 to
0xffff and the update happens between low and high part reads or after high part read.
Read Invalid
Address Value
0x1e2a 0x0000 change after this
0x1e2b 0x0000
0x1e2a 0xffff
0x1e2b 0x0000
Read Valid
Address Value
0x1e2a 0x0000
0x1e2b 0x0001 change after this
0x1e2a 0xffff
0x1e2b 0x0000
No Update
Address Value
0x1e2a 0x0000
0x1e2b 0x0001
0x1e2a 0x0000
0x1e2b 0x0001
Version: 1.20, 2012-12-03 60