Re: [M100] REXCPM battery

2023-09-25 Thread Brian K. White
On 9/22/23 18:09, Brian White wrote: > Took some measurements > > This is with the BAT54C diodes. > > > While not installed in 100: > BATT  2.99v > RAM_RST  2.91v 7uA > SRAM VCC  2.76v > > > While installed in 100, power on, wall power, original tandy 6v adapter: > RAM_RST  4.85v > BATT, installed

[M100] REXCPM battery

2023-09-22 Thread Brian White
Took some measurements This is with the BAT54C diodes. While not installed in 100: BATT 2.99v RAM_RST 2.91v 7uA SRAM VCC 2.76v While installed in 100, power on, wall power, original tandy 6v adapter: RAM_RST 4.85v BATT, installed 3.0v BATT, not installed 3.65v 0.5uA bkw

Re: [M100] rexcpm battery

2023-09-22 Thread Ken St. Cyr
🙂 //Ken From: M100 on behalf of Brian K. White Sent: Thursday, September 21, 2023 10:53 PM To: m100@lists.bitchin100.com Subject: Re: [M100] rexcpm battery I've been reading about charging protection for lithium coin cells, and I think we might want to swap out the BAT54

Re: [M100] rexcpm battery

2023-09-21 Thread Brian K. White
PM *To:* m100@lists.bitchin100.com *Subject:* Re: [M100] rexcpm battery I have repaired my REXCPM and now the github readme includes pics that show a good way to mount a qwiic connector and where to connect bodge wires if you want to take on the challenge of such small loose wires going to such sma

Re: [M100] rexcpm battery

2023-09-20 Thread Brian K. White
...@gmail.com>> *Sent:* Tuesday, September 19, 2023 10:18 PM *To:* m100@lists.bitchin100.com <mailto:m100@lists.bitchin100.com> mailto:m100@lists.bitchin100.com>> *Subject:* Re: [M100] rexcpm battery I have repaired my REXCPM and now the github readme includes pic

Re: [M100] rexcpm battery

2023-09-20 Thread Stephen Adolph
rian K. > White > *Sent:* Tuesday, September 19, 2023 10:18 PM > *To:* m100@lists.bitchin100.com > *Subject:* Re: [M100] rexcpm battery > > I have repaired my REXCPM and now the github readme includes pics that > show a good way to mount a qwiic connector and where to connect bod

Re: [M100] rexcpm battery

2023-09-20 Thread Ken St. Cyr
behalf of Brian K. White Sent: Tuesday, September 19, 2023 10:18 PM To: m100@lists.bitchin100.com Subject: Re: [M100] rexcpm battery I have repaired my REXCPM and now the github readme includes pics that show a good way to mount a qwiic connector and where to connect bodge wires if you want to t

Re: [M100] rexcpm battery

2023-09-19 Thread Brian K. White
I have repaired my REXCPM and now the github readme includes pics that show a good way to mount a qwiic connector and where to connect bodge wires if you want to take on the challenge of such small loose wires going to such small places. All 4 solder points are at least a reasonable chip leg, n

Re: [M100] rexcpm battery

2023-09-19 Thread Brian K. White
White *Sent:* Thursday, September 14, 2023 10:16 PM *To:* m100@lists.bitchin100.com *Subject:* Re: [M100] rexcpm battery On 9/14/23 21:27, Brian K. White wrote: But somehow there is power differential between gnd and vmem (or whatever the positive side of the big cap is, I say vmem because obviousl

Re: [M100] rexcpm battery

2023-09-17 Thread Ken St. Cyr
und wire directly to the REXCPM, though I'm sure most normal people would prefer to have it on a connector. //Ken S. From: M100 on behalf of Brian K. White Sent: Thursday, September 14, 2023 10:16 PM To: m100@lists.bitchin100.com Subject: Re: [M100] rexcpm ba

Re: [M100] rexcpm battery

2023-09-14 Thread Brian K. White
On 9/14/23 21:27, Brian K. White wrote: But somehow there is power differential between gnd and vmem (or whatever the positive side of the big cap is, I say vmem because obviously it powers the sram) on the rexcpm, and 0.7uA of current flowing along RAM_RST. 7uA not 0.7uA! -- bkw

Re: [M100] rexcpm battery

2023-09-14 Thread Brian K. White
also the updated design is visible here https://github.com/bkw777/REXCPM_UPS The schematic now also documents which pins are which on the rexcpm too just for convenience & reference. You *could* got ahead and export gerbers and order boards right now without waiting. But I have a set on the wa

Re: [M100] rexcpm battery

2023-09-14 Thread Brian K. White
-wire version, which adds the ground pin... And you’re saying the only reason it works outside the unit right now without the ground path is because there’s leakage on the RAM_RST line? I'd like to give it a shot ... have you done a prototype run of the 4x battery board yet? //Ken S

Re: [M100] rexcpm battery

2023-09-14 Thread Brian K. White
-wire version, which adds the ground pin... And you’re saying the only reason it works outside the unit right now without the ground path is because there’s leakage on the RAM_RST line? I'd like to give it a shot ... have you done a prototype run of the 4x battery board yet? //Ken S

Re: [M100] rexcpm battery

2023-09-14 Thread Ken St. Cyr
m100@lists.bitchin100.com Subject: Re: [M100] rexcpm battery Let's give THIS a try... https://photos.app.goo.gl/JaSofoK2VotHzVco9 The connector is a standard JST-SH, and cables are available pre-made in both 2" for the 100 and 12" for the 102 or 200. There's even an off-the-shelf cable t

Re: [M100] rexcpm battery

2023-09-13 Thread Brian K. White
Let's give THIS a try... https://photos.app.goo.gl/JaSofoK2VotHzVco9 The connector is a standard JST-SH, and cables are available pre-made in both 2" for the 100 and 12" for the 102 or 200. There's even an off-the-shelf cable that has dupont sockets on one end, so you could connect to an unmodi

Re: [M100] rexcpm battery

2023-09-12 Thread Brian K. White
100 on behalf of Brian K. White *Date: *Monday, September 11, 2023 at 2:28 AM *To: *m...@bitchin100.com *Subject: *[M100] rexcpm battery I thought I made the slickest thing. https://github.com/bkw777/REXCPM_UPS <https://github.com/bkw777/REXCPM_UPS> https://photos.app.goo.gl/i87E4wzimexCR3wL

Re: [M100] rexcpm battery

2023-09-11 Thread Brian K. White
ehalf of Brian K. White *Date: *Monday, September 11, 2023 at 2:28 AM *To: *m...@bitchin100.com *Subject: *[M100] rexcpm battery I thought I made the slickest thing. https://github.com/bkw777/REXCPM_UPS <https://github.com/bkw777/REXCPM_UPS> https://photos.app.goo.gl/i87E4wzimexCR3wL6 &

Re: [M100] rexcpm battery

2023-09-11 Thread Ken St. Cyr
circuit… maybe a jumper that you could remove if you have the REXCPM UPS hooked up //Ken From: M100 on behalf of Brian K. White Date: Monday, September 11, 2023 at 2:28 AM To: m...@bitchin100.com Subject: [M100] rexcpm battery I thought I made the slickest thing. https://github.com/bkw777

[M100] rexcpm battery

2023-09-10 Thread Brian K. White
I thought I made the slickest thing. https://github.com/bkw777/REXCPM_UPS https://photos.app.goo.gl/i87E4wzimexCR3wL6 I was able to get 60mah of battery onto the system bus interface board for REXCPM, and theoretically that should be able to keep the sram memory for at least a year, but it loo