Aurix 2G: HSM SAHMEM window usage

[User18904]

Hello,

I would like to confirm if my understanding is correct about SAHMEM window usage for Aurix 2G HSM.

1) Is it correct to write that HSM writes host base address in SAHBASE at address 0xF00400C0 and then HSM reads or writes data at address 0xF005xxxx?
(For example if last 64k of DSPRAM is reserved and HSM wants to access 5th word, HSM writes 0xD0020000 in SAHBASE and reads or writes at address 0xF0050010?)

2) Is there a mechanism to handle simultaneous access by Host and HSM? (with the example : Host writes at address 0xD0020010 and HSM reads at address 0xF0050010?)

Thanks.

[cwunder · Accepted solution]

The SAHBASE is generally only used during development and its purpose if for a host to access memory locations inside the HSM.  In principal the HSM can access any memory location on the device. If you want to share memory with the HSM usually your software running on the HSM would accept a base address from the host for data exchanges. Two master cannot write to the same location at the same time. The hardware will stall one of the accesses until it is free.