b43-dasm: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/b43-dasm - from package: b43-tools

You may install the required package with command yum install {package}

Error in other languages:
b43-dasm: bevel nie gevind nie
b43-dasm: comandă negăsită
b43-dasm: comando não encontrado
b43-dasm: commande introuvable
b43-dasm: command not found
b43-dasm: käsku ei ole
b43-dasm: không tìm thấy lệnh
b43-dasm: komanda nerasta
b43-dasm: Kommando nicht gefunden.
b43-dasm: kommandot finns inte
b43-dasm: komut yok
b43-dasm: nie znaleziono polecenia
b43-dasm: níor aimsíodh an t-ordú
b43-dasm: no se encontró la orden
b43-dasm: no s'ha trobat l'ordre
b43-dasm: opdracht niet gevonden
b43-dasm: parancs nem található
b43-dasm: perintah tidak ditemukan
b43-dasm: príkaz nenájdený
b43-dasm: příkaz nenalezen
b43-dasm: команда не найдена
b43-dasm: командата не е открита
b43-dasm: 命令找不到
b43-dasm: コマンドが見つかりません