cannot do a "show running-config" on a 3810v

[kerrow]

I have two 3810v, both with 12-1(3a) software and I can not do a show running-config nor a write term command. I am seeing numerous buffer and memory failures, which usually points to an IOS issue. However, I am using this old of IOS to support VoHDLC and do not wish to change from VoHDLC if at all possible for phone system reasons.

[thomas.chen]

This looks like some other issue not related to IOS. As you say you were using VoHDLC then it means there is some buffer overflow or CPU or memory issues.