Using Seeed CAN_BUS Shield and Botletics SIM7000A Shield simultaneously on an Arduino UNO enabling CAN_BUS control of CH4100 charger for my Zero Motorcycle and also internet access for the Arduino with Verizon's cell towers allowing me to monitor the charging remotely through Adafruit IO.
Note: The Seeed CAN_BUS Shield and Botletics SIM7000A Shield both use pins 9, 10, and 11 on the Arduino. The Seeed Shield uses them for SPI and the Botletics Shield uses them for Software Serial. To make these stackable, I broke off the male pins for 9,10, and 11 from the Botletics Shield and then simply used male-male jumpers to connect pins 10 and 11 to 4 and 5 on the female side. I stacked the Seeed on top of the Arduino and then the Botletics on top of the Seeed (with the 10,11 - 4,5 jumpers above that. I also have Vin jumpered to 5V which allows me to power everything through the DB9 port on the Seeed.
Also had to break off the reset pin from the SIM7000 shield because it kept resetting after I powered down the Arduino. *Update:This ^ is still an issue. I just decided to feed power to the SIM7000 with a diode (I'm using an NTE125 diode. no battery. It's working fine now.
Issues to work out:
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If there's a comm issue, it stops sending messages to the charger (so it turns off). *This is mostly resolved
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The battery on the SIM7000A shield means it will stay on after the 5v power is removed. (I've been powering this from the 240v in from the charging station so this isn't ideal. ***This is resolved. I removed the battery and jumpered a diode (NTE125) from Vin to Vbat (My Vin is 5v).
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I always had issues with the CANBUS shield not turning on properly (I always had to power cycle the arduino after charger was powered to get it to work properly. I'm guessing this may be more problematic with the stacked shields but I don't know. So far I've only tested this with arduino usb in power (from startup). **Still working on this. Tried numerous methods of resetting Shield and arduino but still no luck. Started a thread in the Seeed Forum, we'll see how that goes...