[Stm32flash] Write to SRAM?

Searched the archives and didn't see any mention of this not being supported. And doing so appears to be supported as documented in ST's AN3155 App note. I first tried the canned Ubuntu binary version 0.5, no dice. Then pulled the git repo to build version 0.7, same result. No screening of address was apparent in a quick check of the source for a read command and further suggests the device (STM32F103C8 -- likely a clone) is returning an error from stm32_read_memory(). Before pursuing this further I figured I'd ask if this is a known issue without a resolution. Reads of flash and internal bootrom work fine but attempts to access the SRAM fail. Any clarity much appreciated.