[SunHELP] SS20 SBus & burst modes (Re: [rescue] A SBus card for SPARCstation designed in 2020...)

[Romain Dolbeau]

Hello,

Trying to improve my SBusFPGA design & NetBSD driver, I hit on an
interesting (?) question: the status of 64-bits extended transfers
(and even 32-bits 16-words burst) on the SPARCstation 20. The full
details are in the NetBSD port-sparc mailing list there:
<https://mail-index.netbsd.org/port-sparc/2020/12/18/msg002291.html>.

Short version: some Sun document and a PROM attribute say yes, NetBSD
code and lack of Solaris support say no, my guess is 'somewhere in
between' (yes device-to-device, no device-to|from-memory).

Anyone here that could shine some light on the subject?

Cordially,

-- 
Romain Dolbeau