working on gmbitbang

Author: geohot

board/drivers/can.h

@@ -461,14 +461,83 @@ void CAN3_SCE_IRQHandler() { can_sce(CAN3); }
 
 #endif
 
+void set_bitbanged_gmlan(int val) {
+  if (val) {
+    GPIOB->ODR |= (1 << 13);
+  } else {
+    GPIOB->ODR &= ~(1 << 13);
+  }
+}
+
+void bitbang_gmlan(CAN_FIFOMailBox_TypeDef *to_bang) {
+  puts("called bitbang_gmlan\n");
+  puth(can_num_lookup[3]);
+  puts("\n");
+  char test_pkt[] = \
+    {0, // SOF
+     0,0,0,0, // ID10-ID7
+     1, // bitstuff
+     0,0,1,0,1,0,0,   // ID6-ID0
+     0, // RTR
+     0, // IDE
+     0, // reserved
+     1, // bitstuff
+     0,0,0,1, // len
+     0,0,0,0,0, // 1st byte 7-3
+     1, // bitstuff
+     0,0,1,     // 1st byte 2-0
+
+     // start CRC
+     0,1,0,0,0,0,1,1,0,0,0,0,0,
+     1, // bitstuff
+     0,0, // CRC field
+     1,  // CRC delimiter
+
+     1,  // ACK
+     1,  // ACK delimiter
+     1,1,1,1,1,1,1, // EOF
+     1,1,1, // IFS
+     };
+  /*char test_pkt[] = {
+  0,1,0,1, 0,1,0,1, 0,1,0,1,
+  1,1,1,1,
+  0,1,0,1, 0,1,0,1, 0,1,0,1,
+  0,0,0,0,0,0,0,0,
+  0,1,0,1, 0,1,0,1, 0,1,0,1,
+  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+  0,1,0,1, 0,1,0,1, 0,1,0,1,};*/
+
+  #define SPEEED 30
+
+  // bitbang loop
+  set_bitbanged_gmlan(1); // recessive
+  set_gpio_mode(GPIOB, 13, MODE_OUTPUT);
+  enter_critical_section();
+  int init = TIM2->CNT;
+  for (int i = 0; i < sizeof(test_pkt); i++) {
+    while ((TIM2->CNT - init) < (SPEEED*i));
+    set_bitbanged_gmlan(test_pkt[i]);
+  }
+  exit_critical_section();
+  set_gpio_mode(GPIOB, 13, MODE_INPUT);
+
+  puts("bitbang done\n");
+}
+
 void can_send(CAN_FIFOMailBox_TypeDef *to_push, uint8_t bus_number) {
   if (safety_tx_hook(to_push) && !can_autobaud_enabled[bus_number]) {
-    if (bus_number < BUS_MAX) {
-      // add CAN packet to send queue
-      // bus number isn't passed through
-      to_push->RDTR &= 0xF;
-      can_push(can_queues[bus_number], to_push);
-      process_can(CAN_NUM_FROM_BUS_NUM(bus_number));
+    //if (bus_number == 3) { //&& can_num_lookup[3] == -1) {
+    // TODO: why uint8 bro? only int8?
+    if (bus_number == 3 && can_num_lookup[3] == 0xFF) {
+      bitbang_gmlan(to_push);
+    } else {
+      if (bus_number < BUS_MAX) {
+        // add CAN packet to send queue
+        // bus number isn't passed through
+        to_push->RDTR &= 0xF;
+        can_push(can_queues[bus_number], to_push);
+        process_can(CAN_NUM_FROM_BUS_NUM(bus_number));
+      }
     }
   }
 }

tests/gmbitbang/test.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env python
+import time
+from panda import Panda
+
+p1 = Panda('430026000951363338383037')
+p2 = Panda('380016000551363338383037')
+
+# this is a test, no safety
+p1.set_safety_mode(Panda.SAFETY_ALLOUTPUT)
+p2.set_safety_mode(Panda.SAFETY_ALLOUTPUT)
+
+# get versions
+print(p1.get_version())
+print(p2.get_version())
+
+# this sets bus 2 to actually be GMLAN
+p2.set_gmlan(bus=2)
+
+# send w bitbang then without
+p1.set_gmlan(bus=None)
+p1.can_send(20, "\x01", bus=3)
+p1.set_gmlan(bus=2)
+p1.can_send(20, "\x01", bus=3)
+#time.sleep(0.1)
+#p1.set_gmlan(bus=None)
+#p1.can_send(20, "\x01", bus=3)
+
+# test echo
+# (to send on GMLAN, set bus=3)
+time.sleep(0.1)
+print p2.can_recv()
+