From 195af47289761be82eeb4f6687a65f5ee8f38611 Mon Sep 17 00:00:00 2001
From: "roel@libnfc.org" <roel@libnfc.org@ef4ab9da-24cd-11de-8aaa-f3a34680c41f>
Date: Wed, 3 Apr 2013 08:45:04 +0000
Subject: [PATCH 1/1] removed redundant function to compose reader short frame
---
armsrc/hitag2.c | 4 --
armsrc/iso14443a.c | 107 +++++++++++++--------------------------------
armsrc/util.c | 4 ++
armsrc/util.h | 1 +
4 files changed, 36 insertions(+), 80 deletions(-)
diff --git a/armsrc/hitag2.c b/armsrc/hitag2.c
index aa9ce237..1a0e9b56 100644
--- a/armsrc/hitag2.c
+++ b/armsrc/hitag2.c
@@ -29,10 +29,6 @@ bool bAuthenticating;
bool bPwd;
bool bSuccessful;
-size_t nbytes(size_t nbits) {
- return (nbits/8)+((nbits%8)>0);
-}
-
int LogTraceHitag(const uint8_t * btBytes, int iBits, int iSamples, uint32_t dwParity, int bReader)
{
// Return when trace is full
diff --git a/armsrc/iso14443a.c b/armsrc/iso14443a.c
index ca7c3ba4..5a01178d 100644
--- a/armsrc/iso14443a.c
+++ b/armsrc/iso14443a.c
@@ -1262,68 +1262,9 @@ static void TransmitFor14443a(const uint8_t *cmd, int len, int *samples, int *wa
}
//-----------------------------------------------------------------------------
-// Code a 7-bit command without parity bit
-// This is especially for 0x26 and 0x52 (REQA and WUPA)
+// Prepare reader command (in bits, support short frames) to send to FPGA
//-----------------------------------------------------------------------------
-void ShortFrameFromReader(const uint8_t bt)
-{
- int j;
- int last;
- uint8_t b;
-
- ToSendReset();
-
- // Start of Communication (Seq. Z)
- ToSend[++ToSendMax] = SEC_Z;
- last = 0;
-
- b = bt;
- for(j = 0; j < 7; j++) {
- if(b & 1) {
- // Sequence X
- ToSend[++ToSendMax] = SEC_X;
- last = 1;
- } else {
- if(last == 0) {
- // Sequence Z
- ToSend[++ToSendMax] = SEC_Z;
- }
- else {
- // Sequence Y
- ToSend[++ToSendMax] = SEC_Y;
- last = 0;
- }
- }
- b >>= 1;
- }
-
- // End of Communication
- if(last == 0) {
- // Sequence Z
- ToSend[++ToSendMax] = SEC_Z;
- }
- else {
- // Sequence Y
- ToSend[++ToSendMax] = SEC_Y;
- last = 0;
- }
- // Sequence Y
- ToSend[++ToSendMax] = SEC_Y;
-
- // Just to be sure!
- ToSend[++ToSendMax] = SEC_Y;
- ToSend[++ToSendMax] = SEC_Y;
- ToSend[++ToSendMax] = SEC_Y;
-
- // Convert from last character reference to length
- ToSendMax++;
-}
-
-//-----------------------------------------------------------------------------
-// Prepare reader command to send to FPGA
-//
-//-----------------------------------------------------------------------------
-void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
+void CodeIso14443aBitsAsReaderPar(const uint8_t * cmd, int bits, uint32_t dwParity)
{
int i, j;
int last;
@@ -1335,12 +1276,14 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
ToSend[++ToSendMax] = SEC_Z;
last = 0;
+ size_t bytecount = nbytes(bits);
// Generate send structure for the data bits
- for (i = 0; i < len; i++) {
+ for (i = 0; i < bytecount; i++) {
// Get the current byte to send
b = cmd[i];
+ size_t bitsleft = MIN((bits-(i*8)),8);
- for (j = 0; j < 8; j++) {
+ for (j = 0; j < bitsleft; j++) {
if (b & 1) {
// Sequence X
ToSend[++ToSendMax] = SEC_X;
@@ -1358,19 +1301,22 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
b >>= 1;
}
- // Get the parity bit
- if ((dwParity >> i) & 0x01) {
- // Sequence X
- ToSend[++ToSendMax] = SEC_X;
- last = 1;
- } else {
- if (last == 0) {
- // Sequence Z
- ToSend[++ToSendMax] = SEC_Z;
+ // Only transmit (last) parity bit if we transmitted a complete byte
+ if (j == 8) {
+ // Get the parity bit
+ if ((dwParity >> i) & 0x01) {
+ // Sequence X
+ ToSend[++ToSendMax] = SEC_X;
+ last = 1;
} else {
- // Sequence Y
- ToSend[++ToSendMax] = SEC_Y;
- last = 0;
+ if (last == 0) {
+ // Sequence Z
+ ToSend[++ToSendMax] = SEC_Z;
+ } else {
+ // Sequence Y
+ ToSend[++ToSendMax] = SEC_Y;
+ last = 0;
+ }
}
}
}
@@ -1396,6 +1342,14 @@ void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
ToSendMax++;
}
+//-----------------------------------------------------------------------------
+// Prepare reader command to send to FPGA
+//-----------------------------------------------------------------------------
+void CodeIso14443aAsReaderPar(const uint8_t * cmd, int len, uint32_t dwParity)
+{
+ CodeIso14443aBitsAsReaderPar(cmd,len*8,dwParity);
+}
+
//-----------------------------------------------------------------------------
// Wait for commands from reader
// Stop when button is pressed (return 1) or field was gone (return 2)
@@ -1598,7 +1552,8 @@ void ReaderTransmitShort(const uint8_t* bt)
int wait = 0;
int samples = 0;
- ShortFrameFromReader(*bt);
+// ShortFrameFromReader(*bt);
+ CodeIso14443aBitsAsReaderPar(bt,7,0);
// Select the card
TransmitFor14443a(ToSend, ToSendMax, &samples, &wait);
diff --git a/armsrc/util.c b/armsrc/util.c
index 3870a6c6..f2298290 100644
--- a/armsrc/util.c
+++ b/armsrc/util.c
@@ -12,6 +12,10 @@
#include "util.h"
#include "string.h"
+size_t nbytes(size_t nbits) {
+ return (nbits/8)+((nbits%8)>0);
+}
+
uint32_t SwapBits(uint32_t value, int nrbits) {
int i;
uint32_t newvalue = 0;
diff --git a/armsrc/util.h b/armsrc/util.h
index d2a85ba0..ac141065 100644
--- a/armsrc/util.h
+++ b/armsrc/util.h
@@ -27,6 +27,7 @@
#define BUTTON_DOUBLE_CLICK -2
#define BUTTON_ERROR -99
+size_t nbytes(size_t nbits);
uint32_t SwapBits(uint32_t value, int nrbits);
void num_to_bytes(uint64_t n, size_t len, uint8_t* dest);
uint64_t bytes_to_num(uint8_t* src, size_t len);
--
2.39.5