//Arduino 1.8.3
//STM32F103C,  64k flash
//upload method: serial (A9 to RX, A10 to TX)
//To upload set Boot0 jumper to 1 (the one further away from reset btn) and press reset (stm will boot from flash wich contains uart to flash uploader)
//upload via arduino IDE
//To boot program after restart set Boot0 jumper to 0

//#define DEBUG

//pins die nicht gehn als output:
/* PA15
 * PB3
 * PB4
 * PA12
 */

#define SCAN_0 PA1
#define SCAN_1 PA2
#define SCAN_2 PA3
#define SCAN_3 PA4
#define SCAN_4 PA5
#define SCAN_5 PA6
#define SCAN_6 PA7
#define SCAN_7 PB0
#define SCAN_8 PB1
#define IN_A PB13 //geht
#define IN_B PB14 //geht
#define IN_C PB15 //geht
#define IN_D PB5 //geht
#define IN_E PB6 //geht
#define IN_F PB7 //geht
#define IN_G PB8 //geht
#define IN_H PB9 //geht

#define PIN_LED PC13

#define PIN_COIL_SENSE PB11

#define LEDON LOW
#define LEDOFF HIGH


#define NUM_SCANPINS 9


int scanaddress[]={SCAN_0,SCAN_1,SCAN_2,SCAN_3,SCAN_4,SCAN_5,SCAN_6,SCAN_7,SCAN_8};
int inaddress[]={IN_A,IN_B,IN_C,IN_D,IN_E,IN_F,IN_G,IN_H};

byte keymatrix[128][NUM_SCANPINS]={
//0   1   2   3   4   5   6   7   8
{255,255,255,255,255,255,255,255,255}, //0 =  [NULL]
{255,255,255,255,255,255,255,255,255}, //1 = [START OF HEADING]
{255,255,255,255,255,255,255,255,255}, //2 = [START OF TEXT]
{255,255,255,255,255,255,255,255,255}, //3 = [END OF TEXT]
{255,255,255,255,255,255,255,255,255}, //4 = [END OF TRANSMISSION]
{255,255,255,255,255,255,255,255,255}, //5 = [ENQUIRY]
{255,255,255,255,255,255,255,255,255}, //6 = [ACKNOWLEDGE]
{255,255,255,255,255,255,255,255,255}, //7 = [BELL]
{255,6,255,255,255,255,255,255,255}, //8 = [BACKSPACE]
{255,255,255,255,255,255,255,255,255}, //9 =   [HORIZONTAL TAB]
{255,2,255,255,255,255,255,255,255}, //10 = [LINE FEED]

{255,255,255,255,255,255,255,255,255}, //11 = [VERTICAL TAB]
{255,255,255,255,255,255,255,255,255}, //12 = [FORM FEED]
{255,2,255,255,255,255,255,255,255}, //13 = [CARRIAGE RETURN]

{255,255,255,255,255,255,255,255,255}, //14 = [SHIFT OUT]
{255,255,255,255,255,255,255,255,255}, //15 = [SHIFT IN]
{255,255,255,255,255,255,255,255,255}, //16 = [DATA LINK ESCAPE]
{255,255,255,255,255,255,255,255,255}, //17 = [DEVICE CONTROL 1]
{255,255,255,255,255,255,255,255,255}, //18 = [DEVICE CONTROL 2]

{255,255,255,255,255,255,255,255,255}, //19 = [DEVICE CONTROL 3]
{255,255,255,255,255,255,255,255,255}, //20 = [DEVICE CONTROL 4]
{255,255,255,255,255,255,255,255,255}, //21 = [NEGATIVE ACKNOWLEDGE]
{255,255,255,255,255,255,255,255,255}, //22 = [SYNCHRONOUS IDLE]
{255,255,255,255,255,255,255,255,255}, //23 = [END OF TRANS. BLOCK]
{255,255,255,255,255,255,255,255,255}, //24 = [CANCEL]
{255,255,255,255,255,255,255,255,255}, //25 = [END OF MEDIUM]
{255,255,255,255,255,255,255,255,255}, //26 = [SUBSTITUTE]
{255,255,255,255,255,255,255,255,255}, //27 = [ESCAPE]
{255,255,255,255,255,255,255,255,255}, //28 = [FILE SEPARATOR]
{255,255,255,255,255,255,255,255,255}, //29 = [GROUP SEPARATOR]
{255,255,255,255,255,255,255,255,255}, //30 = [RECORD SEPARATOR]
{255,255,255,255,255,255,255,255,255}, //31 = [UNIT SEPARATOR]
{255,7,255,255,255,255,255,255,255}, //32 =  [SPACE]   //H7  H=1 = 7
{7,255,255,255,255,255,255,6,255}, //33 = !
{7,255,255,255,255,255,255,255,5}, //34 = "
{255,255,255,255,255,255,255,5,255}, //35 = #
{7,255,255,255,255,255,255,255,4}, //36 = $
{7,255,255,255,255,255,255,3,255}, //37 = %
{7,255,255,255,255,255,255,255,3}, //38 = &
{7,255,255,255,255,255,255,5,255}, //39 = '
{7,255,255,255,255,255,255,255,0}, //40 = (
{7,255,255,255,255,255,255,1,255}, //41 = )
{7,255,255,255,255,255,255,255,7}, //42 = *
{255,255,255,255,255,255,255,255,7}, //43 = +
{255,255,255,255,7,255,255,255,255}, //44 = ,
{255,255,255,7,255,255,255,255,255}, //45 = -
{255,255,255,255,255,7,255,255,255}, //46 = .
{7,255,255,255,255,255,255,0,255}, //47 = /
{255,255,255,255,255,255,255,255,1}, //48 = 0
{255,255,255,255,255,255,255,6,255}, //49 = 1
{255,255,255,255,255,255,255,255,5}, //50 = 2
{255,255,255,255,255,255,255,4,255}, //51 = 3
{255,255,255,255,255,255,255,255,4}, //52 = 4
{255,255,255,255,255,255,255,3,255}, //53 = 5
{255,255,255,255,255,255,255,255,3}, //54 = 6
{255,255,255,255,255,255,255,0,255}, //55 = 7
{255,255,255,255,255,255,255,255,0}, //56 = 8
{255,255,255,255,255,255,255,1,255}, //57 = 9
{7,255,255,255,255,7,255,255,255}, //58 = :
{7,255,255,255,7,255,255,255,255}, //59 = ;
{255,255,255,255,255,255,255,255,255}, //60 = <
{7,255,255,255,255,255,255,255,1}, //61 = =
{255,255,255,255,255,255,255,255,255}, //62 = >
{7,255,255,255,255,255,255,2,255}, //63 = ?
{255,255,255,255,255,255,255,255,255}, //64 = @
{7,255,255,255,255,2,255,255,255}, //65 = A
{7,255,255,255,6,255,255,255,255}, //66 = B
{7,255,255,255,5,255,255,255,255}, //67 = C
{7,255,255,255,255,3,255,255,255}, //68 = D
{7,255,255,255,255,255,5,255,255}, //69 = E
{7,255,255,255,255,5,255,255,255}, //70 = F
{7,255,255,255,255,4,255,255,255}, //71 = G
{7,255,255,255,255,6,255,255,255}, //72 = H
{7,255,255,6,255,255,255,255,255}, //73 = I
{7,255,255,255,255,0,255,255,255}, //74 = J
{7,255,255,255,255,255,0,255,255}, //75 = K
{7,255,255,255,255,255,1,255,255}, //76 = L
{7,255,255,255,0,255,255,255,255}, //77 = M
{7,255,255,255,2,255,255,255,255}, //78 = N
{7,255,255,255,255,255,2,255,255}, //79 = O
{7,255,255,2,255,255,255,255,255}, //80 = P
{7,255,255,255,255,255,3,255,255}, //81 = Q
{7,255,255,5,255,255,255,255,255}, //82 = R
{7,255,255,255,255,1,255,255,255}, //83 = S
{7,255,255,255,255,255,4,255,255}, //84 = T
{7,255,255,255,255,255,6,255,255}, //85 = U
{7,255,255,255,4,255,255,255,255}, //86 = V
{7,255,255,3,255,255,255,255,255}, //87 = W
{7,255,255,255,3,255,255,255,255}, //88 = X
{7,255,255,255,1,255,255,255,255}, //89 = Y
{7,255,255,4,255,255,255,255,255}, //90 = Z
{255,255,255,255,255,255,255,255,255}, //91 = [
{255,255,255,255,255,255,255,255,255}, //92 = '\'
{255,255,255,255,255,255,255,255,255}, //93 = ]
{255,255,255,255,255,255,255,255,255}, //94 = ^
{7,255,255,7,255,255,255,255,255}, //95 = _
{7,255,255,255,255,255,255,255,2}, //96 = `
{255,255,255,255,255,2,255,255,255}, //97 = a
{255,255,255,255,6,255,255,255,255}, //98 = b
{255,255,255,255,5,255,255,255,255}, //99 = c
{255,255,255,255,255,3,255,255,255}, //100 = d
{255,255,255,255,255,255,5,255,255}, //101 = e
{255,255,255,255,255,5,255,255,255}, //102 = f
{255,255,255,255,255,4,255,255,255}, //103 = g
{255,255,255,255,255,6,255,255,255}, //104 = h
{255,255,255,6,255,255,255,255,255}, //105 = i
{255,255,255,255,255,0,255,255,255}, //106 = j
{255,255,255,255,255,255,0,255,255}, //107 = k
{255,255,255,255,255,255,1,255,255}, //108 = l
{255,255,255,255,0,255,255,255,255}, //109 = m
{255,255,255,255,2,255,255,255,255}, //110 = n
{255,255,255,255,255,255,2,255,255}, //111 = o
{255,255,255,2,255,255,255,255,255}, //112 = p
{255,255,255,255,255,255,3,255,255}, //113 = q
{255,255,255,5,255,255,255,255,255}, //114 = r
{255,255,255,255,255,1,255,255,255}, //115 = s
{255,255,255,255,255,255,4,255,255}, //116 = t
{255,255,255,255,255,255,6,255,255}, //117 = u
{255,255,255,255,4,255,255,255,255}, //118 = v
{255,255,255,3,255,255,255,255,255}, //119 = w
{255,255,255,255,3,255,255,255,255}, //120 = x
{255,255,255,255,1,255,255,255,255}, //121 = y
{255,255,255,4,255,255,255,255,255}, //122 = z
{255,255,255,255,255,255,255,255,255}, //123 = {
{255,5,255,255,255,255,6,255,255}, //124 = |  CODE+u
{255,255,255,255,255,255,255,255,255}, //125 = }
{255,255,255,255,255,255,255,255,255}, //126 = ~
{255,255,255,255,255,255,255,255,255} //127 = [DEL}


};


byte keymatrix195[256][NUM_SCANPINS]= {//matrix for 2 byte characters starting with 195

{255,255,255,255,255,255,255,255,255}, // 195,0 = 
{255,255,255,255,255,255,255,255,255}, // 195,1 = 
{255,255,255,255,255,255,255,255,255}, // 195,2 = 
{255,255,255,255,255,255,255,255,255}, // 195,3 = 
{255,255,255,255,255,255,255,255,255}, // 195,4 = 
{255,255,255,255,255,255,255,255,255}, // 195,5 = 
{255,255,255,255,255,255,255,255,255}, // 195,6 = 
{255,255,255,255,255,255,255,255,255}, // 195,7 = 
{255,255,255,255,255,255,255,255,255}, // 195,8 = 
{255,255,255,255,255,255,255,255,255}, // 195,9 = 
{255,255,255,255,255,255,255,255,255}, // 195,10 = 
{255,255,255,255,255,255,255,255,255}, // 195,11 = 
{255,255,255,255,255,255,255,255,255}, // 195,12 = 
{255,255,255,255,255,255,255,255,255}, // 195,13 = 
{255,255,255,255,255,255,255,255,255}, // 195,14 = 
{255,255,255,255,255,255,255,255,255}, // 195,15 = 
{255,255,255,255,255,255,255,255,255}, // 195,16 = 
{255,255,255,255,255,255,255,255,255}, // 195,17 = 
{255,255,255,255,255,255,255,255,255}, // 195,18 = 
{255,255,255,255,255,255,255,255,255}, // 195,19 = 
{255,255,255,255,255,255,255,255,255}, // 195,20 = 
{255,255,255,255,255,255,255,255,255}, // 195,21 = 
{255,255,255,255,255,255,255,255,255}, // 195,22 = 
{255,255,255,255,255,255,255,255,255}, // 195,23 = 
{255,255,255,255,255,255,255,255,255}, // 195,24 = 
{255,255,255,255,255,255,255,255,255}, // 195,25 = 
{255,255,255,255,255,255,255,255,255}, // 195,26 = 
{255,255,255,255,255,255,255,255,255}, // 195,27 = 
{255,255,255,255,255,255,255,255,255}, // 195,28 = 
{255,255,255,255,255,255,255,255,255}, // 195,29 = 
{255,255,255,255,255,255,255,255,255}, // 195,30 = 
{255,255,255,255,255,255,255,255,255}, // 195,31 = 
{255,255,255,255,255,255,255,255,255}, // 195,32 = 
{255,255,255,255,255,255,255,255,255}, // 195,33 = 
{255,255,255,255,255,255,255,255,255}, // 195,34 = 
{255,255,255,255,255,255,255,255,255}, // 195,35 = 
{255,255,255,255,255,255,255,255,255}, // 195,36 = 
{255,255,255,255,255,255,255,255,255}, // 195,37 = 
{255,255,255,255,255,255,255,255,255}, // 195,38 = 
{255,255,255,255,255,255,255,255,255}, // 195,39 = 
{255,255,255,255,255,255,255,255,255}, // 195,40 = 
{255,255,255,255,255,255,255,255,255}, // 195,41 = 
{255,255,255,255,255,255,255,255,255}, // 195,42 = 
{255,255,255,255,255,255,255,255,255}, // 195,43 = 
{255,255,255,255,255,255,255,255,255}, // 195,44 = 
{255,255,255,255,255,255,255,255,255}, // 195,45 = 
{255,255,255,255,255,255,255,255,255}, // 195,46 = 
{255,255,255,255,255,255,255,255,255}, // 195,47 = 
{255,255,255,255,255,255,255,255,255}, // 195,48 = 
{255,255,255,255,255,255,255,255,255}, // 195,49 = 
{255,255,255,255,255,255,255,255,255}, // 195,50 = 
{255,255,255,255,255,255,255,255,255}, // 195,51 = 
{255,255,255,255,255,255,255,255,255}, // 195,52 = 
{255,255,255,255,255,255,255,255,255}, // 195,53 = 
{255,255,255,255,255,255,255,255,255}, // 195,54 = 
{255,255,255,255,255,255,255,255,255}, // 195,55 = 
{255,255,255,255,255,255,255,255,255}, // 195,56 = 
{255,255,255,255,255,255,255,255,255}, // 195,57 = 
{255,255,255,255,255,255,255,255,255}, // 195,58 = 
{255,255,255,255,255,255,255,255,255}, // 195,59 = 
{255,255,255,255,255,255,255,255,255}, // 195,60 = 
{255,255,255,255,255,255,255,255,255}, // 195,61 = 
{255,255,255,255,255,255,255,255,255}, // 195,62 = 
{255,255,255,255,255,255,255,255,255}, // 195,63 = 
{255,255,255,255,255,255,255,255,255}, // 195,64 = 
{255,255,255,255,255,255,255,255,255}, // 195,65 = 
{255,255,255,255,255,255,255,255,255}, // 195,66 = 
{255,255,255,255,255,255,255,255,255}, // 195,67 = 
{255,255,255,255,255,255,255,255,255}, // 195,68 = 
{255,255,255,255,255,255,255,255,255}, // 195,69 = 
{255,255,255,255,255,255,255,255,255}, // 195,70 = 
{255,255,255,255,255,255,255,255,255}, // 195,71 = 
{255,255,255,255,255,255,255,255,255}, // 195,72 = 
{255,255,255,255,255,255,255,255,255}, // 195,73 = 
{255,255,255,255,255,255,255,255,255}, // 195,74 = 
{255,255,255,255,255,255,255,255,255}, // 195,75 = 
{255,255,255,255,255,255,255,255,255}, // 195,76 = 
{255,255,255,255,255,255,255,255,255}, // 195,77 = 
{255,255,255,255,255,255,255,255,255}, // 195,78 = 
{255,255,255,255,255,255,255,255,255}, // 195,79 = 
{255,255,255,255,255,255,255,255,255}, // 195,80 = 
{255,255,255,255,255,255,255,255,255}, // 195,81 = 
{255,255,255,255,255,255,255,255,255}, // 195,82 = 
{255,255,255,255,255,255,255,255,255}, // 195,83 = 
{255,255,255,255,255,255,255,255,255}, // 195,84 = 
{255,255,255,255,255,255,255,255,255}, // 195,85 = 
{255,255,255,255,255,255,255,255,255}, // 195,86 = 
{255,255,255,255,255,255,255,255,255}, // 195,87 = 
{255,255,255,255,255,255,255,255,255}, // 195,88 = 
{255,255,255,255,255,255,255,255,255}, // 195,89 = 
{255,255,255,255,255,255,255,255,255}, // 195,90 = 
{255,255,255,255,255,255,255,255,255}, // 195,91 = 
{255,255,255,255,255,255,255,255,255}, // 195,92 = 
{255,255,255,255,255,255,255,255,255}, // 195,93 = 
{255,255,255,255,255,255,255,255,255}, // 195,94 = 
{255,255,255,255,255,255,255,255,255}, // 195,95 = 
{255,255,255,255,255,255,255,255,255}, // 195,96 = 
{255,255,255,255,255,255,255,255,255}, // 195,97 = 
{255,255,255,255,255,255,255,255,255}, // 195,98 = 
{255,255,255,255,255,255,255,255,255}, // 195,99 = 
{255,255,255,255,255,255,255,255,255}, // 195,100 = 
{255,255,255,255,255,255,255,255,255}, // 195,101 = 
{255,255,255,255,255,255,255,255,255}, // 195,102 = 
{255,255,255,255,255,255,255,255,255}, // 195,103 = 
{255,255,255,255,255,255,255,255,255}, // 195,104 = 
{255,255,255,255,255,255,255,255,255}, // 195,105 = 
{255,255,255,255,255,255,255,255,255}, // 195,106 = 
{255,255,255,255,255,255,255,255,255}, // 195,107 = 
{255,255,255,255,255,255,255,255,255}, // 195,108 = 
{255,255,255,255,255,255,255,255,255}, // 195,109 = 
{255,255,255,255,255,255,255,255,255}, // 195,110 = 
{255,255,255,255,255,255,255,255,255}, // 195,111 = 
{255,255,255,255,255,255,255,255,255}, // 195,112 = 
{255,255,255,255,255,255,255,255,255}, // 195,113 = 
{255,255,255,255,255,255,255,255,255}, // 195,114 = 
{255,255,255,255,255,255,255,255,255}, // 195,115 = 
{255,255,255,255,255,255,255,255,255}, // 195,116 = 
{255,255,255,255,255,255,255,255,255}, // 195,117 = 
{255,255,255,255,255,255,255,255,255}, // 195,118 = 
{255,255,255,255,255,255,255,255,255}, // 195,119 = 
{255,255,255,255,255,255,255,255,255}, // 195,120 = 
{255,255,255,255,255,255,255,255,255}, // 195,121 = 
{255,255,255,255,255,255,255,255,255}, // 195,122 = 
{255,255,255,255,255,255,255,255,255}, // 195,123 = 
{255,255,255,255,255,255,255,255,255}, // 195,124 = 
{255,255,255,255,255,255,255,255,255}, // 195,125 = 
{255,255,255,255,255,255,255,255,255}, // 195,126 = 
{255,255,255,255,255,255,255,255,255}, // 195,127 = 
{255,255,255,255,255,255,255,255,255}, // 195,128 = 
{255,255,255,255,255,255,255,255,255}, // 195,129 = 
{255,255,255,255,255,255,255,255,255}, // 195,130 = 
{255,255,255,255,255,255,255,255,255}, // 195,131 = 
{7,255,255,255,255,255,255,7,255}, // 195,132 = Ä
{255,255,255,255,255,255,255,255,255}, // 195,133 = 
{255,255,255,255,255,255,255,255,255}, // 195,134 = 
{255,255,255,255,255,255,255,255,255}, // 195,135 = 
{255,255,255,255,255,255,255,255,255}, // 195,136 = 
{255,255,255,255,255,255,255,255,255}, // 195,137 = 
{255,255,255,255,255,255,255,255,255}, // 195,138 = 
{255,255,255,255,255,255,255,255,255}, // 195,139 = 
{255,255,255,255,255,255,255,255,255}, // 195,140 = 
{255,255,255,255,255,255,255,255,255}, // 195,141 = 
{255,255,255,255,255,255,255,255,255}, // 195,142 = 
{255,255,255,255,255,255,255,255,255}, // 195,143 = 
{255,255,255,255,255,255,255,255,255}, // 195,144 = 
{255,255,255,255,255,255,255,255,255}, // 195,145 = 
{255,255,255,255,255,255,255,255,255}, // 195,146 = 
{255,255,255,255,255,255,255,255,255}, // 195,147 = 
{255,255,255,255,255,255,255,255,255}, // 195,148 = 
{255,255,255,255,255,255,255,255,255}, // 195,149 = 
{7,255,255,255,255,255,7,255,255}, // 195,150 = Ö
{255,255,255,255,255,255,255,255,255}, // 195,151 = 
{255,255,255,255,255,255,255,255,255}, // 195,152 = 
{255,255,255,255,255,255,255,255,255}, // 195,153 = 
{255,255,255,255,255,255,255,255,255}, // 195,154 = 
{255,255,255,255,255,255,255,255,255}, // 195,155 = 
{7,255,255,255,255,255,255,255,6}, // 195,156 = Ü
{255,255,255,255,255,255,255,255,255}, // 195,157 = 
{255,255,255,255,255,255,255,255,255}, // 195,158 = 
{255,255,255,255,255,255,255,2,255}, // 195,159 = ß
{255,255,255,255,255,255,255,255,255}, // 195,160 = 
{255,255,255,255,255,255,255,255,255}, // 195,161 = 
{255,255,255,255,255,255,255,255,255}, // 195,162 = 
{255,255,255,255,255,255,255,255,255}, // 195,163 = 
{255,255,255,255,255,255,255,7,255}, // 195,164 = ä
{255,255,255,255,255,255,255,255,255}, // 195,165 = 
{255,255,255,255,255,255,255,255,255}, // 195,166 = 
{255,255,255,255,255,255,255,255,255}, // 195,167 = 
{255,255,255,255,255,255,255,255,255}, // 195,168 = 
{255,255,255,255,255,255,255,255,255}, // 195,169 = 
{255,255,255,255,255,255,255,255,255}, // 195,170 = 
{255,255,255,255,255,255,255,255,255}, // 195,171 = 
{255,255,255,255,255,255,255,255,255}, // 195,172 = 
{255,255,255,255,255,255,255,255,255}, // 195,173 = 
{255,255,255,255,255,255,255,255,255}, // 195,174 = 
{255,255,255,255,255,255,255,255,255}, // 195,175 = 
{255,255,255,255,255,255,255,255,255}, // 195,176 = 
{255,255,255,255,255,255,255,255,255}, // 195,177 = 
{255,255,255,255,255,255,255,255,255}, // 195,178 = 
{255,255,255,255,255,255,255,255,255}, // 195,179 = 
{255,255,255,255,255,255,255,255,255}, // 195,180 = 
{255,255,255,255,255,255,255,255,255}, // 195,181 = 
{255,255,255,255,255,255,7,255,255}, // 195,182 = ö
{255,255,255,255,255,255,255,255,255}, // 195,183 = 
{255,255,255,255,255,255,255,255,255}, // 195,184 = 
{255,255,255,255,255,255,255,255,255}, // 195,185 = 
{255,255,255,255,255,255,255,255,255}, // 195,186 = 
{255,255,255,255,255,255,255,255,255}, // 195,187 = 
{255,255,255,255,255,255,255,255,6}, // 195,188 = ü
{255,255,255,255,255,255,255,255,255}, // 195,189 = 
{255,255,255,255,255,255,255,255,255}, // 195,190 = 
{255,255,255,255,255,255,255,255,255}, // 195,191 = 
{255,255,255,255,255,255,255,255,255}, // 195,192 = 
{255,255,255,255,255,255,255,255,255}, // 195,193 = 
{255,255,255,255,255,255,255,255,255}, // 195,194 = 
{255,255,255,255,255,255,255,255,255}, // 195,195 = 
{255,255,255,255,255,255,255,255,255}, // 195,196 = 
{255,255,255,255,255,255,255,255,255}, // 195,197 = 
{255,255,255,255,255,255,255,255,255}, // 195,198 = 
{255,255,255,255,255,255,255,255,255}, // 195,199 = 
{255,255,255,255,255,255,255,255,255}, // 195,200 = 
{255,255,255,255,255,255,255,255,255}, // 195,201 = 
{255,255,255,255,255,255,255,255,255}, // 195,202 = 
{255,255,255,255,255,255,255,255,255}, // 195,203 = 
{255,255,255,255,255,255,255,255,255}, // 195,204 = 
{255,255,255,255,255,255,255,255,255}, // 195,205 = 
{255,255,255,255,255,255,255,255,255}, // 195,206 = 
{255,255,255,255,255,255,255,255,255}, // 195,207 = 
{255,255,255,255,255,255,255,255,255}, // 195,208 = 
{255,255,255,255,255,255,255,255,255}, // 195,209 = 
{255,255,255,255,255,255,255,255,255}, // 195,210 = 
{255,255,255,255,255,255,255,255,255}, // 195,211 = 
{255,255,255,255,255,255,255,255,255}, // 195,212 = 
{255,255,255,255,255,255,255,255,255}, // 195,213 = 
{255,255,255,255,255,255,255,255,255}, // 195,214 = 
{255,255,255,255,255,255,255,255,255}, // 195,215 = 
{255,255,255,255,255,255,255,255,255}, // 195,216 = 
{255,255,255,255,255,255,255,255,255}, // 195,217 = 
{255,255,255,255,255,255,255,255,255}, // 195,218 = 
{255,255,255,255,255,255,255,255,255}, // 195,219 = 
{255,255,255,255,255,255,255,255,255}, // 195,220 = 
{255,255,255,255,255,255,255,255,255}, // 195,221 = 
{255,255,255,255,255,255,255,255,255}, // 195,222 = 
{255,255,255,255,255,255,255,255,255}, // 195,223 = 
{255,255,255,255,255,255,255,255,255}, // 195,224 = 
{255,255,255,255,255,255,255,255,255}, // 195,225 = 
{255,255,255,255,255,255,255,255,255}, // 195,226 = 
{255,255,255,255,255,255,255,255,255}, // 195,227 = 
{255,255,255,255,255,255,255,255,255}, // 195,228 = 
{255,255,255,255,255,255,255,255,255}, // 195,229 = 
{255,255,255,255,255,255,255,255,255}, // 195,230 = 
{255,255,255,255,255,255,255,255,255}, // 195,231 = 
{255,255,255,255,255,255,255,255,255}, // 195,232 = 
{255,255,255,255,255,255,255,255,255}, // 195,233 = 
{255,255,255,255,255,255,255,255,255}, // 195,234 = 
{255,255,255,255,255,255,255,255,255}, // 195,235 = 
{255,255,255,255,255,255,255,255,255}, // 195,236 = 
{255,255,255,255,255,255,255,255,255}, // 195,237 = 
{255,255,255,255,255,255,255,255,255}, // 195,238 = 
{255,255,255,255,255,255,255,255,255}, // 195,239 = 
{255,255,255,255,255,255,255,255,255}, // 195,240 = 
{255,255,255,255,255,255,255,255,255}, // 195,241 = 
{255,255,255,255,255,255,255,255,255}, // 195,242 = 
{255,255,255,255,255,255,255,255,255}, // 195,243 = 
{255,255,255,255,255,255,255,255,255}, // 195,244 = 
{255,255,255,255,255,255,255,255,255}, // 195,245 = 
{255,255,255,255,255,255,255,255,255}, // 195,246 = 
{255,255,255,255,255,255,255,255,255}, // 195,247 = 
{255,255,255,255,255,255,255,255,255}, // 195,248 = 
{255,255,255,255,255,255,255,255,255}, // 195,249 = 
{255,255,255,255,255,255,255,255,255}, // 195,250 = 
{255,255,255,255,255,255,255,255,255}, // 195,251 = 
{255,255,255,255,255,255,255,255,255}, // 195,252 = 
{255,255,255,255,255,255,255,255,255}, // 195,253 = 
{255,255,255,255,255,255,255,255,255}, // 195,254 = 
{255,255,255,255,255,255,255,255,255} // 195,255 = 

};

#define TEXTBUFFERSIZE 8192
byte textbuffer[TEXTBUFFERSIZE]; //ca 60-65 Zeilen pro DinA4, a 65 characters (10 Pica), 78 characters (12 Elite) or 97 characters (15 Mikron)
uint16_t bufferpos_write=0;
uint16_t bufferpos_read=0;


#define DELAY_KEYPRESS 100 //delay in ms between keypresses
long last_keypress=0;

volatile uint16_t count_bufferedchars=0; //keeps track of buffered characters on the typewriter
#define MAX_TYPEWRITER_BUFFERCOUNT 2
#define MAXIMUM_COILWAIT 5000 //if no interrupt from coil received decrease buffer count after this time (in ms)

void setup() {
  Serial.begin(9600);
  pinMode(SCAN_0,INPUT_PULLUP);
  pinMode(SCAN_1,INPUT_PULLUP);
  pinMode(SCAN_2,INPUT_PULLUP);
  pinMode(SCAN_3,INPUT_PULLUP);
  pinMode(SCAN_4,INPUT_PULLUP);
  pinMode(SCAN_5,INPUT_PULLUP);
  pinMode(SCAN_6,INPUT_PULLUP);
  pinMode(SCAN_7,INPUT_PULLUP);
  pinMode(SCAN_8,INPUT_PULLUP);

  pinMode(IN_A,OUTPUT);
  pinMode(IN_B,OUTPUT);
  pinMode(IN_C,OUTPUT);
  pinMode(IN_D,OUTPUT);
  pinMode(IN_E,OUTPUT);
  pinMode(IN_F,OUTPUT);
  pinMode(IN_G,OUTPUT);
  pinMode(IN_H,OUTPUT);

  digitalWrite(IN_A,LOW);
  digitalWrite(IN_B,LOW);
  digitalWrite(IN_C,LOW);
  digitalWrite(IN_D,LOW);
  digitalWrite(IN_E,LOW);
  digitalWrite(IN_F,LOW);
  digitalWrite(IN_G,LOW);
  digitalWrite(IN_H,LOW);

  pinMode(PIN_COIL_SENSE, INPUT_PULLUP);
  attachInterrupt(PIN_COIL_SENSE, coilInterrupt, RISING); //pin pulled low if coil powered
  

  pinMode(PIN_LED,OUTPUT);
  digitalWrite(PIN_LED,LEDON);
  delay(500);
  digitalWrite(PIN_LED,LEDOFF);

  //Serial.println("Brother AX-240 Serialmod"); 
  
}

void loop() {
  checkSerial(); //check serial buffer and write to textbuffer
  
  if (millis()>last_keypress+DELAY_KEYPRESS){
    
    if (count_bufferedchars<MAX_TYPEWRITER_BUFFERCOUNT) //wait if too many chars are send to typewriter buffer
    {
      bool charsend=checkTextbuffer(); //check one character from serial buffer and send to typewriter
      //Serial.print(6); //Send ACK
      if (charsend){ //a character was actually sent
        last_keypress=millis();
      }
    }
    
    if (count_bufferedchars>0 && millis()>last_keypress+MAXIMUM_COILWAIT){ //coil response timeout
      count_bufferedchars--; //decrease buffer count
      last_keypress=millis();
    }
    
  }

  if (count_bufferedchars>=MAX_TYPEWRITER_BUFFERCOUNT){
    digitalWrite(PIN_LED,LEDON); //led on -> wait for buffer to empty
  }else{
    digitalWrite(PIN_LED,LEDOFF); //led off -> buffer isnt full
  }
}

void checkSerial(){
  while(Serial.available()){
    if (Serial.available()>0){
      char c=Serial.read();
      bufferpos_write++; 
      bufferpos_write%=TEXTBUFFERSIZE;
      textbuffer[bufferpos_write]=c; //bufferpos_write points to last written char position
    }
  }
}

bool textAvailable(){
  if (bufferpos_write!=bufferpos_read){
    return true;
  }
  return false;
}

bool checkTextbuffer(){
  bool returnvalue=false;
  //while(Serial.available()){
    //if (Serial.available()>0){
    if (textAvailable()) { //buffer contains unread chars
      bufferpos_read++;//bufferpos_read points to last read char position
      bufferpos_read%=TEXTBUFFERSIZE;
      char c = textbuffer[bufferpos_read]; 
      
      #ifdef DEBUG 
        Serial.print((uint8_t)c); //echo
        Serial.print("="); //echo
        Serial.println(c); //echo
      #endif

      if (c==195 || c==194) { //umlaut
        #ifdef DEBUG 
          Serial.print("Uml:");
        #endif
        
        while (!textAvailable()){ checkSerial(); } //wait for next byte and checkSerial in between
        bufferpos_read++;//bufferpos_read points to last read char position
        bufferpos_read%=TEXTBUFFERSIZE;
        char c2=textbuffer[bufferpos_read]; 
        #ifdef DEBUG 
          Serial.println((uint8_t)c2); //echo
        #endif
        sendChar(c,c2); //2 byte character
        returnvalue=true;
        
      }else{
        sendChar(c,0); //normal 1 byte character
        returnvalue=true;
      }


    }
  //}

  
  return returnvalue; //true= character send, false=buffer was empty
}

void sendChar(char c,char c2) { //c2 =0 for 1 byte characters
  uint8_t keypress[NUM_SCANPINS]={255,255,255,255,255,255,255,255,255}; //keypress contains id of input pin. 255=not pressed, A=0, B=1 ...

  //check if key is implemented (not all 255,255,255,..)
  bool keyimplemented=false;
  for (uint8_t i=0;i<NUM_SCANPINS;i++){
    if (keymatrix[c][i]!=255){
      keyimplemented=true;
    }
  }

  if (keyimplemented && ( (c>=32 && c<127) || c==10 || c==13 ) ) { //1 byte char
    #ifdef DEBUG
    Serial.println("1 byte char");
    #endif
    for (uint8_t i=0;i<NUM_SCANPINS;i++){
      keypress[i]=keymatrix[c][i]; //copy keypress connections for current char
    }
  }else if (c==195){ //umlauts
    #ifdef DEBUG 
      Serial.println("2 byte char");
    #endif
    for (uint8_t i=0;i<NUM_SCANPINS;i++){
      keypress[i]=keymatrix195[c2][i]; //copy keypress connections for current char
    }
  }else if(c==194){ //others
    if (c2==167){ // §
      keypress[0]=7; keypress[7]=4; //shift + 3
    }else if (c2==176){ // °
      keypress[1]=5; keypress[3]=3; //CODE + W
    }
  }else if(c>=32){ //not recognized character (everything else) and not a control command
    keypress[1]=7; // [SPACE]  //print space to keep text aligned
  }

  unsigned int scanaddr;
  unsigned int inaddr;


  //Update count buffered chars
  if ((c>32 && c<127) ) { //pressed key uses hammer. (32 is space)
    if (keyimplemented){ //keymatrix was implemented for c (not 255,255...)
      count_bufferedchars++; //character send to typewriter. Increase character buffer count
    }
  }

  //digitalWrite(PIN_LED,LEDON);
  #define HOLDCYCLES 3

  for (uint8_t hold=0;hold<HOLDCYCLES;hold++){ //cycles to hold the key
    for (uint8_t i=0;i<NUM_SCANPINS;i++){
      if (keypress[i]!=255){ //some key on scan i will be pressed
        scanaddr=scanaddress[i]; //geht pin address for i   SCAN_i
        inaddr=inaddress[keypress[i]];
      
        while(digitalRead(scanaddr)){ }//wait while high
        //if (!digitalRead(scanaddr)){ //scanaddr is scanned
          digitalWrite(inaddr,HIGH); 
          while(!digitalRead(scanaddr)){  } //wait while low
          digitalWrite(inaddr,LOW); //set high -> transistor pulls input of printer to ground
        //}
  
      }
    }
  }

  
  //digitalWrite(PIN_LED,LEDOFF);
}

void coilInterrupt(){
  if (count_bufferedchars>0){
    count_bufferedchars--;
  }
}