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Hi, first of all I must say that I'm a Java and C programmer (well... still a student) and I don't know pretty much anything about ASM, but not willing to power my core with 6.2V, and before blaming it on the LCD I thought that maybe I could look for some timing issues in the LCD init procedure so I was looking into the ASM code in mios_cldc.inc and I tried to add: movlw 1 ; 1 ms delay call MIOS_Delay right after the labels of the MIOS_CLCD_Strobe_Set and MIOS_CLCD_Strobe_Clr routines (I used MIOS_Delay because adding tens of nop lead to nothing). And guess what my LCD started working at every startup, I can see the characters appear with a delay. Obviously I think that that's the dirtiest hack ever done and I admit that I have no idea about possible side effects, I already noticed some problems after uploading new applications the core won't reboot. I'm asking some of the more knowledgeable people if my findings have any meaning and could be used to solve my problem. Thanks. Paolo Link to the datasheet of the Displaytech LCD: http://www.displaytech.com.hk/pdf/char/202a%20series-v11.PDF showing timing diagrams.

Hi, well no I din't mean that, the 7805 was fed with the appropriate tension to regulate it's nominal 5V output, but these 5V weren't enough for the circuit I had to remove the regulator and feed the cirucuit with at least 6.2VDC from my bench variable PSU. Regards. Paolo Garuti Edit: I've just finished testing my core with another LCD, Ampire 2x16, and it worked without problems with the on board 5V PSU, so it may be that my 2x20 is faulty. Is anyone using the Displaytech 202A with success? I'm not sure if it's a good idea to permanently run my core at 6.2V even if the datasheet of the PIC gives 7.5 as absolute maximum rating.

Hi, Thank you gentlemen for your replies. My Core with 1 DIN, 1 DOUT, 1 Bankstick, and the Displaytech 202A 2x20 LCD attached, needs at least 6.2V to correctly initialize the display. I'm not sure if it's a good idea to permanently run my core at 6.2V even if the datasheet of the PIC gives 7.5 as absolute maximum rating. Thanks. Best regards. Paolo

Hi, yes I used the feedback, and I also uploaded "mios_v1_9c_pic18f452.hex" successfully. After a series of reboots I was able to see the "READY." msg but on the next reboot the LCD didn't initialize. If I upload an application it works, I see the MIDI output and when the LCD initialises correctly I can see the "GUI". I'm currently testing the Core module with LCD, 1 DIN, 1DOUT, 1 Bankstick attached, AINs clamped to GND, anything else unconnected, except the MIDI ports, but I also tested it with just the LCD and got the same results, is it OK? Regards. Paolo

Well, during the upload of MIOS using the file update_without_installed_mios.hex (v1.9c) I've got the following messages: Starting upload of update_without_installed_mios.hex Hex file contains code in MIOS range, forcing reboot! Received error code 01: Less bytes than expected have been received This was an expected error - please ignore! Received Upload Request Sending block 00000000-000000FF Received error code 05: Write access failed (invalid address range) - used by 1st level bsl ... but after that the upload process didn't stop and after the whole file was sent I received: 00000005694764 ms | [D0 1A 00] Channel 1: Channel Pressure value: 26 which means that the bootloader was installed successfully, as I read in a post by Thorsten. After that, rebooting the core produces: 00000006883224 ms | Sysex message: F0 00 00 7E 40 00 01 F7 00000006885120 ms | [D0 1A 00] Channel 1: Channel Pressure value: 26 and the LCD is uninitialized showing the black first row. The key pressure countdown messages shown in the readme sect. A didn't show up though. If I upload an application it works i.e. ain64_din128_dout128 V2.0 sends DIN changes as MIDI msgs, but the LCD does get initialized only "once in a while", I cannot specify after how many reboots or after how long it has been shut down because it seems random!? Thanks Paolo

Hi, I read every single post about LCDs on the forum but I haven't been able to get this working. I'm using a Displaytech 202A 2x20 LCD that I got from Mike's Shop (so I'm supposing that it's fully compatible with MIOS) along with a preprogrammed PIC, uploaded MIOS (update_without_installed_mios.hex v1.9c) without problems it's up and running responding with the right sysx msg upon query, the LCD though presents the uninitialised black first row screen "most of the time", yes because every once in a while it initializes correctly showing the Copyright msg and the application screen, the application is always running OK even when the LCD isn't as the core sends MIDI msgs on DIN toggles. This "once in a while" isn't deterministic, even waiting for the caps to discharge before re-applying power doesn't imply that it will work (ruling out reset problems??). The connection between core and LCD has been tested millions of times and is correct, the LCD doesn't seem broken as when it initialises it is stable and works correctly. Vdd on the LCD is 4.97V, RS 3.06V, after startup; during startup with the LCD cable not connected core R/W pin toggles with a 3V swing E pin 5V swing, but with the cable connected the swing is only 0.3V-0.7V even if there are no shorts. Sending: (communication with the LCD) F0 00 00 7E 40 00 0D 02 00 0B 0A 00 00 00 01 00 00 00 00 F7 Returns: F0 00 00 7E 40 00 0F 04 00 F7 Sending: (LCD type, MIDI interface, core frequency) F0 00 00 7E 40 00 0D 02 00 00 00 00 00 00 01 00 00 00 00 F7 Returns: F0 00 00 7E 40 00 0F 01 00 F7 Sending: (LCD option #1 and #2) F0 00 00 7E 40 00 0D 02 00 0A 78 00 00 00 02 00 00 00 00 F7 Returns: F0 00 00 7E 40 00 0F 03 07 02 04 F7 Sending: (LCD timeout state) F0 00 00 7E 40 00 0D 02 00 0B 12 00 00 00 02 00 00 00 00 F7 Returns: F0 00 00 7E 40 00 0F 0F 07 0F 07 F7 I'm lost, please help. Thank you in advance. Regards. Paolo