m68hc12-as: command not found

Have You tried accessing the binary with the full path?

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 Debian possible default full paths are:

/usr/bin/m68hc12-as - from package: binutils-m68hc1x

You may install the required package with command apt-get install {package}
Error in other languages:
m68hc12-as: bevel nie gevind nie
m68hc12-as: comandă negăsită
m68hc12-as: comando não encontrado
m68hc12-as: commande introuvable
m68hc12-as: command not found
m68hc12-as: käsku ei ole
m68hc12-as: không tìm thấy lệnh
m68hc12-as: komanda nerasta
m68hc12-as: Kommando nicht gefunden.
m68hc12-as: kommandot finns inte
m68hc12-as: komut yok
m68hc12-as: nie znaleziono polecenia
m68hc12-as: níor aimsíodh an t-ordú
m68hc12-as: no se encontró la orden
m68hc12-as: no s'ha trobat l'ordre
m68hc12-as: opdracht niet gevonden
m68hc12-as: parancs nem található
m68hc12-as: perintah tidak ditemukan
m68hc12-as: príkaz nenájdený
m68hc12-as: příkaz nenalezen
m68hc12-as: команда не найдена
m68hc12-as: командата не е открита
m68hc12-as: 命令找不到
m68hc12-as: コマンドが見つかりません