const char smtp_220[4] = 
/* "220" */
{0x32, 0x32, 0x30, };
const char smtp_helo[6] = 
/* "HELO " */
{0x48, 0x45, 0x4c, 0x4f, 0x20, };
const char smtp_mail_from[12] = 
/* "MAIL FROM: " */
{0x4d, 0x41, 0x49, 0x4c, 0x20, 0x46, 0x52, 0x4f, 0x4d, 0x3a, 0x20, };
const char smtp_rcpt_to[10] = 
/* "RCPT TO: " */
{0x52, 0x43, 0x50, 0x54, 0x20, 0x54, 0x4f, 0x3a, 0x20, };
const char smtp_data[7] = 
/* "DATA\r\n" */
{0x44, 0x41, 0x54, 0x41, 0xd, 0xa, };
const char smtp_to[5] = 
/* "To: " */
{0x54, 0x6f, 0x3a, 0x20, };
const char smtp_from[7] = 
/* "From: " */
{0x46, 0x72, 0x6f, 0x6d, 0x3a, 0x20, };
const char smtp_subject[10] = 
/* "Subject: " */
{0x53, 0x75, 0x62, 0x6a, 0x65, 0x63, 0x74, 0x3a, 0x20, };
const char smtp_quit[7] = 
/* "QUIT\r\n" */
{0x51, 0x55, 0x49, 0x54, 0xd, 0xa, };
const char smtp_crnl[3] = 
/* "\r\n" */
{0xd, 0xa, };
const char smtp_crnlperiodcrnl[6] = 
/* "\r\n.\r\n" */
{0xd, 0xa, 0x2e, 0xd, 0xa, };