z80dasm: 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/z80dasm - from package: z80dasm

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

On Debian possible default full paths are:

/usr/bin/z80dasm - from package: z80dasm

You may install the required package with command apt-get install {package}

Error in other languages:
z80dasm: bevel nie gevind nie
z80dasm: comandă negăsită
z80dasm: comando não encontrado
z80dasm: commande introuvable
z80dasm: command not found
z80dasm: käsku ei ole
z80dasm: không tìm thấy lệnh
z80dasm: komanda nerasta
z80dasm: Kommando nicht gefunden.
z80dasm: kommandot finns inte
z80dasm: komut yok
z80dasm: nie znaleziono polecenia
z80dasm: níor aimsíodh an t-ordú
z80dasm: no se encontró la orden
z80dasm: no s'ha trobat l'ordre
z80dasm: opdracht niet gevonden
z80dasm: parancs nem található
z80dasm: perintah tidak ditemukan
z80dasm: príkaz nenájdený
z80dasm: příkaz nenalezen
z80dasm: команда не найдена
z80dasm: командата не е открита
z80dasm: 命令找不到
z80dasm: コマンドが見つかりません