+/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: t -*- */
/*! \file dspic33f.c
\author Scott Livingston
#include "pic.h"
+#define CYCLE_DELAY() delay_ticks(10);
+
//! Handle a PIC command; currently assumes dsPIC33F/PIC24H
void pic_handle_fn( uint8_t const app,
uint8_t const verb,
txdata(app,verb,0);
break;
+ case PIC_CMDLIST:
+ pic33f_cmdlist(len); // reply is handled by pic33f_cmdlist
+ break;
+
default:
debugstr( "Verb unimplemented in PIC application." );
txdata(app,NOK,0);
}
}
+void pic33f_transcmd(unsigned char cmd) {
+ int i = 0;
+ DIR_PGD_WR;
+ CLR_PGC;
+ for (i = 0; i < 4; i++) {
+ if (cmd & 0x1)
+ SET_PGD;
+ else
+ CLR_PGD;
+ CYCLE_DELAY();
+ SET_PGC;
+ cmd >>= 1;
+ CYCLE_DELAY();
+ CLR_PGC;
+ }
+ CLR_PGD;
+}
void pic33f_trans8( unsigned char byte )
{
unsigned int i;
DIR_PGD_WR; // Write mode
- i = 1;
- while (i & 0xff) {
- if (byte & i) {
+ for (i = 0; i < 8; i++) {
+ if (byte & 0x01) {
SET_PGD;
} else {
CLR_PGD;
}
- delay_ticks(10);
+ CYCLE_DELAY();
SET_PGC;
- delay_ticks(10);
+ byte >>= 1;
+ CYCLE_DELAY();
CLR_PGC;
- delay_ticks(10);
- i = i << 1;
+ //CYCLE_DELAY();
}
CLR_PGD;
DIR_PGD_RD; // Read mode
Shift in the instruction. Note that it does not execute until
the next 4 clock cycles (which also corresponds to a command
receipt time). */
- unsigned int i;
- DIR_PGD_WR;
- CLR_PGD;
- CLR_PGC;
- for (i = 0; i < 4; i++) {
- SET_PGC;
- delay_ticks(10);
- CLR_PGC;
- delay_ticks(10);
- }
+ pic33f_transcmd(0);
pic33f_trans16( loww );
pic33f_trans8( highb );
DIR_PGD_RD;
DIR_PGD_WR;
// Shift in command (REGOUT: 0001b).
- SET_PGD;
- delay_ticks(10);
- SET_PGC;
- delay_ticks(10);
- CLR_PGC;
- delay_ticks(10);
-
- CLR_PGD;
- delay_ticks(10);
- for (i = 0; i < 3; i++) {
- SET_PGC;
- delay_ticks(10);
- CLR_PGC;
- delay_ticks(10);
- }
+ pic33f_transcmd(1);
// Pump clock for 8 cycles, and switch PGD direction to read.
for (i = 0; i < 7; i++) {
SET_PGC;
- delay_ticks(10);
+ CYCLE_DELAY();
CLR_PGC;
- delay_ticks(10);
+ CYCLE_DELAY();
}
DIR_PGD_RD;
be read) on falling clock edges. */
for (i = 0; i < 16; i++) {
SET_PGC;
- delay_ticks(10);
+ CYCLE_DELAY();
CLR_PGC;
result |= READ_PGD << i;
- delay_ticks(10);
+ CYCLE_DELAY();
}
-
+#if 1
/* One last tick apparently is needed here, at least by the
dsPIC33FJ128GP708 chip that I am working with. Note that this
is not in the flash programming specs. */
SET_PGC;
- delay_ticks(10);
+ CYCLE_DELAY();
CLR_PGC;
- delay_ticks(10);
+ CYCLE_DELAY();
+#endif
return result;
}
+void pic33f_cmdlist(unsigned int list_len) {
+ /* commands are written as 4-byte little-endian records, where
+ the low 4 bits of first byte contains the command, and the
+ next three bytes contain the data.
+
+ Currently this only supports the SIX and REGOUT
+ instructions.
+
+ SIX instructions return no data. REGOUT instructions return
+ the 16-bit value read as two bytes, lower byte first.
+
+ The final two bytes of the response are the 2's complement
+ inverse of the sum of the response words. i.e., if the
+ response is correctly recieved, the sum of the words should
+ be 0.
+
+ This is sent when the goodfet is done running the command
+ list, and is ready for further commands.
+ */
+
+ unsigned char cmd;
+ unsigned int response_word;
+ unsigned int checksum = 0;
+ int response_count;
+ int i;
+ list_len &= ~3; // truncate to multiple of 4 bytes.
+ if (list_len > CMDDATALEN)
+ list_len = CMDDATALEN;
+ response_count = 1;
+ for (i = 0; i < list_len; i += 4) {
+ cmd = cmddata[i];
+ if (cmd == 0)
+ continue;
+ else if (cmd == 1)
+ response_count ++;
+ else
+ goto error;
+ }
+ txhead(PIC, PIC_CMDLIST, response_count << 1);
+
+ for (i = 0; i < list_len; i+= 4) {
+ cmd = cmddata[i];
+ if (cmd == 0) {
+ // SIX command
+ pic33f_transcmd(0);
+ pic33f_trans8(cmddata[i+1]);
+ pic33f_trans8(cmddata[i+2]);
+ pic33f_trans8(cmddata[i+3]);
+
+ } else if (cmd == 1) {
+ // REGOUT command
+ response_word = pic33f_regout();
+ checksum += response_word;
+ response_count--;
+ txword(response_word);
+ }
+ }
+ txword(~checksum + 1);
+ if (response_count != 1)
+ debugstr("Response count wrong");
+ return;
+ error:
+ txdata(PIC, NOK, 0);
+}
+/* This should be replaced by pic33f_cmdlist */
void pic33f_sixlist( unsigned int list_len )
{
unsigned int k;
}
+/* This is slated to be replaced by pic33f_cmdlist */
unsigned int pic33f_getid()
{
unsigned int result;
CLR_PGC;
for (key_low = 0; key_low < 33; key_low++) {
SET_PGC;
- delay_us(1);
+ CYCLE_DELAY();
CLR_PGC;
- delay_us(1);
+ CYCLE_DELAY();
}
DIR_PGD_RD;
projects / goodfet / blobdiff