The standard of review when an appellant contends his plea was involuntary requires us to consider the totality of the circumstances surrounding the entry of the plea. Gonzales v. State, 963 S.W.2d 844, 846 (Tex. App.--San Antonio 1998, no pet.); Crawford v. State, 890 S.W.2d 941, 944 (Tex. App.--San Antonio 1994, no pet.). We must therefore review the entire record surrounding entry of the plea, including the written stipulations and waivers. Harling v. State, 899 S.W.2d 9, 13 (Tex. App.--San Antonio 1995, pet. ref'd). "When the record reflects that the trial court appropriately admonished the defendant, a prima facie showing that the defendant's guilty plea was knowing and voluntary is established." Rodriguez v. State, 933 S.W.2d 702, 705 (Tex. App.--San Antonio 1996, pet. ref'd). "The burden then shifts to the defendant to prove that he did not understand the consequences of his plea." Id. at 706. This burden is a particularly heavy one when the defendant states he understands the nature of the proceeding and his plea is voluntary. Id.; see also Harling, 899 S.W.2d at 13.