sdld6808: 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 Debian possible default full paths are:

/usr/bin/sdld6808 - from package: sdcc

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

Error in other languages:
sdld6808: bevel nie gevind nie
sdld6808: comandă negăsită
sdld6808: comando não encontrado
sdld6808: commande introuvable
sdld6808: command not found
sdld6808: käsku ei ole
sdld6808: không tìm thấy lệnh
sdld6808: komanda nerasta
sdld6808: Kommando nicht gefunden.
sdld6808: kommandot finns inte
sdld6808: komut yok
sdld6808: nie znaleziono polecenia
sdld6808: níor aimsíodh an t-ordú
sdld6808: no se encontró la orden
sdld6808: no s'ha trobat l'ordre
sdld6808: opdracht niet gevonden
sdld6808: parancs nem található
sdld6808: perintah tidak ditemukan
sdld6808: príkaz nenájdený
sdld6808: příkaz nenalezen
sdld6808: команда не найдена
sdld6808: командата не е открита
sdld6808: 命令找不到
sdld6808: コマンドが見つかりません